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NORMAL    FUNDUS. 


LESSONS  ON  THE  EYE 


FOR  THE  USE  OF 


UNDERGRADUATE  STUDENTS 


BY 

FRANK  L.  HENDERSON,  M.  D. 

EX-PRESIDENT     OF     THE     ST.     LOUIS     MEDICAL     SOCIETY      (1905);    CHAIRMAN     OF     THE 
OPHTHALMIC    SECTION    OF    THE    ST.  LOUIS  MEDICAL  SOCIETY  (iQIo);  OPHTHAL- 
MIC    SURGEON     TO     ST.    MARY's     INFIRMARY;    CONSULTI.N'G    OCULIST   TO 

the  wabash  railway;  member  op  the  american  medical 
association;  member  op  the  Missouri  state  medi- 
cal association;  MEMBER  OP  THE  AMERICAN 
ACADEMY     OF    OPHTHALMOLOGY    AND 
OTO-LARYNGOLOGY,   ETC. 


FOURTH  EDITION,  REVISED 


PHILADELPHIA 

P.   BLAKISTON'S  SON   &  CO 

1012  WALNUT  STREET 
1911 


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V 


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ofnmam  uBwn 

Copyright,  ioio,  by  P.  Blakiston's  Son  &  Co. 


Printed   by 

The  Maple  Press 

York,  Pa. 


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Op  I 


PREFACE  TO  FOURTH  EDITION 


In  revising  this  little  book  the  original  purpose  of 
making  it  a  substitute  for  the  student's  classroom  notes 
has  been  adhered  to.  With  the  ever-increasing  volume 
of  ophthalmic  knowledge  this  has  become  more  difficult. 
The  surcharged  specialist  will  be  able  to  detect  many 
omissions.  Some  of  these  omissions  may  not  have 
been  intentional. 

HuMBOi-DT  Building,  St.  Louis,  Mo. 


1802 


PREFACE  TO  THIRD  EDITION. 


Student's  manuals  on  diseases  of  the  eye  are,  as  a 
rule,  either  exhaustive  treatises  in  fine  print  or  con- 
densations of  the  entire  science  of  ophthalmology.  The 
authors  of  these  works  seem  loath  to  omit  any  knowl- 
edge which,  as  specialists,  they  have  acquired.  The 
result  is  that  subjects  which  the  general  practitioner 
never  attempts  to  master  are  given  as  much  space  as 
those  with  which  he  should  be  familiar. 

It  should  be  the  purpose  of  a  medical  school  to  provide 
its  graduates  with  an  equipment  which  will  best  meet 
the  demands  of  general  practice,  and  I  recognize  that 
there  is  enough  matter  to  fill  the  course  to  overflowing, 
that  is  of  more  importance  than  the  layers  of  the  retina 
or  the  formula  for  calculating  the  index  of  refraction  of 
a  transparent  medium. 

The  only  claim  to  originality  made  for  this  work  lies 
in  its  omissions.  Minute  anatomy,  the  fitting  of  glasses, 
skiascopy,  ophthalmoscopy  and  kindred  subjects  have 
been  left  out  intentionally,  as  I  believe  they  belong 
to  post-graduate  instruction.  I  have  also  slighted 
those  diseases  which  have  to  be  diagnosed  with  the 
ophthalmoscope,  as  I  doubt  the  diagnostic  value  of  an 
ophthalmoscope  in  the  hands  of  the  average  practitioner. 

It  is  not  my  desire  to  minimize  medical  education 
but  rather  to  increase  the  useful  knowledge  of  the 
vii 


Vlll  PREFACE    TO    THIRD    EDITION. 

graduate  by  selecting  that  which  will  be  of  the  most 
service  to  him,  at  the  same  time  giving  him  as  much 
as  the  undergraduate  student  •  can  reasonably  be 
expected  to  learn  in  the  limited  time  allotted  to  the  eye 
in  our  medical  schools.  The  use  of  these  printed  notes 
enables  the  teacher  to  devote  much  time  to  quizzing 
which  would  otherwise  be  spent  in  lecturing.  They 
also  enable  the  student  to  dispense  with  his  inaccurate 
and  misleading  classroom  notes.  The  subject  has  been 
divided  into  twenty-eight  lessons,  or  one  lesson  for 
each  week  of  a  seven  months'  session.  In  the  spelling 
of  such  words  as  oxid,  quinin,  morphin,  sulfate,  etc., 
the  rules  adopted  in  1891,  by  the  American  Association 
for  the  Advancement  of  Science,  have  been  followed. 


CONTENTS. 


LESSON  I. 

ANATOMY. 

The  Orbits;  Ocular  muscles;  Lids. 

LESSON  IL 

ANATOMY  {continued). 

The  Lacrymal  apparatus;  Conjunctiva;  Eyeball;  Cornea. 

LESSON  in. 
ANATOMY  (continued). 
The  Sclera;  Iris;  Ciliary  body;  Choroid. 

LESSON  IV. 
ANATOMY  (continued). 
The  Lens;  Vitreous;  Retina;  Optic  nerves. 

LESSON  V. 

OPTICS. 

Light;  Refraction;  Prisms;  Lenses. 

Convex  lenses;  Concave  lenses;  Cylindric  lenses. 

LESSON  VI. 

REFRACTION    AND    PHYSIOLOGY. 

Emmetropia;  Accommodation;  Presbyopia;  Convergence 
Field  of  vision;  Color  perception. 


X  CONTENTS. 

LESSON  VII. 

ERRORS    OF    REFRACTION. 

Ametropia;  Hyperopia;  Myopia;  Astigmia;  Isometropia; 
Anisometropia;  Antimetropia. 

LESSON  VIII. 

DISORDERS    OF    THE    OCULAR    MOVEMENTS. 

Strabismus;  Paralytic  strabismus. 
LESSON  IX. 

DISORDERS     OF    THE    OCULAR    MOVEMENTS     {cOVltiuued) . 

Comitant  strabismus;  Insufficiency  of  the  ocular  muscles; 
Nystagmus. 

LESSON  X. 

DISEASES    OF    THE    LIDS. 

Blepharitis;  Hordeolum;  Chalazion;  Trichiasis;  Entropion 
and  ectropion;  Ankyloblepharon. 

LESSON  XI. 

DISEASES    OF    THE    LIDS    (cOlltinued). 

Blepharospasm;  Lagophthalmia;  Ptosis;  Eczema;  Herpes 
zoster  ophthalmicus;  Phthiriasis;  Ecchymosis  of  the 
lids;  Rodent  Ulcer;  Sarcoma;  Erysipelas;  Lupus; 
Syphilitic  ulcer. 

LESSON  XII. 

DISEASES    OF    THE    LACRYMAL    APPARATUS. 

Diseases  of  the  lacrymal  gland;  Anomalies  of  the  puncta 
and  canaHculi;  Chronic  dacryocystitis;  Acute  dacryocys- 
titis. 

LESSON  XIII. 

DISEASES    OF    THE    ORBITS. 

Meningocele;  Periostitis;  Caries  and  necrosis;  Hyperostosis; 
Periostosis;  Exostosis;  Injuries;  Orbital  cellulitis; 
Tumors;  Pulsating  exophthalmos. 


CONTENTS.  XI 

LESSON  XIV. 

DISEASES    OF    THE    CONJUNCTIVA. 

Catarrhal  conjunctivitis;  Chronic  catarrhal  conjunctivitis; 
Purulent  conjunctivitis;  Membranous  conjunctivitis. 

LESSON  XV. 
DISEASES  OF  THE  CONJUNCTIVA   (continued). 
Granular   conjunctivitis   or  trachoma;   Acute   trachoma; 
Follicular  conjunctivitis. 

LESSON  XVL 
DISEASES  OF  THE  CONJUNCTIVA   (continued). 
Vernal  conjunctivitis;  Pterygium;  Pinguecula;  Symbleph- 
aron;     Burns;     Sub-conjunctival    ecchymosis;    Morbid 
growths  in  the  conjunctiva. 

LESSON  XVIL 

DISEASES    OF    THE    CORNEA. 

Phlyctenular  keratitis;  Interstitial  keratitis. 

LESSON  XVIII. 
DISEASES  OF  THE  CORNEA   (continued). 
Ulceration  of  the  cornea. 

LESSON  XIX. 

DISEASES    OF    THE    CORNEA    (continued)    AND    SCLERA. 

Vascular  keratitis  or  pannus;  Opacities  of  the  cornea; 
Staphyloma;  Arcus  senilis;  Conical  cornea;  Foreign 
bodies  in  the  cornea;  Episcleritis;  Scleritis. 

LESSON  XX. 

DISEASES    OF    THE    IRIS. 

Mydriasis;  Myosis;  Iritis;  Plastic  iritis;  Suppurative  iritis; 
Serous  iritis. 


Xii  CONTENTS. 

LESSON  XXI. 

DISEASES    OF    THE    CILIARY    BODY    AND    VITREOUS. 

Plastic  and  suppurative  cyclitis;  Serous  cyclitis;  Sympa- 
thetic Ophthalmia;  Muscae  volitantes;  Opacities  of  the 
vitreous;  Hemorrhage  into  the  vitreous;  Foreign  bodies 
in  the  vitreous. 

LESSON  XXIL 

DISEASES    OF    THE    CHOROID. 

Plastic  choroiditis;  Disseminate  choroiditis;  Central  cho- 
roiditis; Syphilitic  choroido-retinitis;  Myopic  choroid- 
itis; Purulent  choroiditis;  Pseudo-glioma;  Panophthal- 
mitis; Rupture  of  the  choroid. 

LESSON  XXIIL 

GLAUCOMA. 

Secretion  and  excretion  of  intra-ocular  fluid;  Tension; 
Simple  glaucoma;  Acute  glaucoma;  Absolute  glaucoma; 
Secondary  glaucoma. 

LESSON  XXIV. 

DISEASES    OF    THE    CRYSTALLINE    LENS. 

Dislocation  of  the  lens;  Cataract;  Aphakia.  . 
LESSON  XXV. 

DISEASES    OF    THE    RETINA. 

Hyperemia  and  anemia;  Retinal  change  from  direct  sun 
rays;  Snow  blindness;  Electric  ophthalmia;  Embolism 
and  thrombosis;  Retinitis;  Albuminuric  retinitis;  Dia- 
betic retinitis;  SyphiUtic  retinitis;  Hemorrhagic  retinitis; 
Retinitis  pigmentosa;  Detachment  of  the  retina; 
Glioma  of  the  retina. 


CONTENTS.  Xlll 

LESSON  XXVI. 

DISEASES    OF    THE    OPTIC    NERVE. 

Papillitis;  Retro-bulbar  neuritis;  Quinin  amblyopia; 
Atrophy  of  the  optic  nerve. 

LESSON  XXVIL 

FUNCTIONAL    DISORDERS    OF    VISION. 

Amblyopia  and  amaurosis;  Amaurosis  partiaHs  fugax; 
Hemianopsia;  Nyctalopia;  Hemeralopia. 

LESSON  xxvin. 

GENERAL    THERAPEUTICS. 

Heat;  Cold;  Anesthesia;  Mydriatics;  Cycloplegics;  Myotics; 
Antiseptics  and  disinfectants;  Stimulants  and  astrin- 
gents; Ointments;  Miscellaneous  remedies. 


LESSON  I. 

ANATOMY  OF  THE  EYE. 

THE    ORBITS. 

These  four-sided,  pyramidal  or  conical  cavities,  a 
little  over  an  inch  and  a  half  deep,  are  formed  by  seven 
bones:  frontal,  sphenoid,  ethmoid,  superior  maxillary, 
])alate.  malar  and  lacrymal.     On  the  inner  wall  of  the 


Fig.  I. — Left  orbit. 

orbit  is  the  groove,  formed  by  the  lacrymal  bone  and 
the  nasal  spine  of  the  superior  maxillary,  in  which  is 
lodged  the  lacrymal  sac.  In  front  of  this  groove  is  the 
insertion  of  the  orbicularis,  the  muscle  which  closes  the 
I 


2  LESSONS    ON    'IHE    EYE. 

eyelids,  and  l>ehind  the  groove  is  the  insertion  of  the 
tensor  tarsi  or  Horner's  muscle  which  holds  the  lids 
close  to  the  globe.  In  the  angle  formed  by  the  roof  of 
the  orbit  and  the  nasal  wall,  and  a  short  distance  be- 
hind the  orbital  rim,  is  the  loop  or  pulley  through  which 
passes  the  tendon  of  the  superior  oblique  muscle.  In 
the  angle  formed  by  the  roof  and  the  temporal  wall  and 
just  under  the  edge  of  the  orbit  is  a  fossa  which  holds 
the  lacrymal  gland.  At  the  junction  of  the  inner  and 
middle  thirds  of  the  superior  orbital  rim  is  the  supra- 
orbital notch  or  foramen  through  which  passes  the  supra- 
orbital nerve,  artery  and  vein.  Below  the  infra-orbital 
rim  is  the  infra-orbital  foramen,  which  is  the  termination 
of  the  canal  of  the  same  name.  Near  the  apex  of  the 
orbit  and  between  the  great  and  lesser  wing  of  the 
sphenoid  bone  is  the  sphenoidal  fissure,  which  transmits 
the  third,  fourth,  the  ophthalmic  division  of  the  fifth 
and  sixth  nerves  and  the  ophthalmic  vein.  The  apex 
of  the  orbit  corresponds  to  the  optic  foramen,  a  cylin- 
drical canal  in  the  lesser  wing  of  the  sphenoid  bone, 
which  transmits  the  optic  nerve  and  ophthalmic  artery. 
Extending  forward  and  outward  from  near  the  apex 
is  the  spheno-maxillary  fissure.  It  lies  between  the 
lower  border  of  the  gi-eat  wing  of  the  sphenoid  bone  and 
the  maxillary  bone,  and  transmits  the  infra-orbital 
vessels  and  several  nerves.  In  the  middle  of  the  orbital 
floor  is  the  infra-orbital  groove  which  terminates  in  the 
infra-orbital  canal.  The  bones  are  covered  by  perios- 
teum and  the  orbital  space  not  filled  by  the  eyeball, 
nerves,  muscles  and  vessels,  is  occupied  by  fat  and 
connective  tissue.  This  connective  tissue  becomes 
thickened  in  parts  so  as  to  form  sheaths  for  the  muscles 


ANATOMY    OF     1111 


and  optic  ncr\-c.  It  also  dcx'clops  a  nu'iiihraiu'  which 
spreads  over  the  eyeball,  from  the  entrance  of  the  o])tic 
nerve  to  within  three  millimeters  of  the  cornea,  where  it 
becomes  inseparably  mingled  with  the  conjunctiva. 
This  membrane  is  called  Tenon's  capsule.  It  is  loosely 
connected  to  the  episclera,  the  space  between  them 
serving  as  a  lymph  channel.  The  ophthalniic  arlcry, 
a  branch  of  the  internal  carotid,  supj)lies  l)lood  to  the 
orbit  and  its  contents. 


Viv,.  2. — The  ocuhir  muscles  seen  from  above,  a,  Superior  ol)lii|ue;  h, 
superior  rectus;  c,  ixlernal  rectus;  (i,  internal  rectus;  e,  optic  nerve; 
f,   pulley  of  su])Crior  oblique;  ,tf,   o])ti(Kimmissure. 


THE    OCl^LAR    MUSCLES. 

The  ocular  muscles  are  six  in  number,  the  internal, 
external,  superior  and  inferior  recti,  and  the  superior 


4  LKSSONS    OF    THE    EYE. 

and  hiferior  oblique.  All  except  the  inferior  oblique 
arise  from  the  apex  of  the  orbit  around  the  optic  fora- 
men. The  inferior  oblique  arises  from  the  floor  of  the 
orbit,  in  a  slight  depression  in  the  superior  maxillary- 
bone,  near  the  lacrymal  groove.  All  the  ocular 
muscles,  after  piercing  the  capsule  of  Tenon  are  in- 
serted in  the  sclera,  the  four  recti  at  points  varying 
from  5  .  5  to  7  .  5  millimeters  from  the  cornea. 


Fig. 


-Muscles  of  the  left  eve. 


Though  the  superior  oblique  arises  at  the  apex  of  the 
orbit,  the  direction  of  its  force  is  changed  by  passing 
through  the  pulley,  before  mentioned,  which  is  situated 
in  the  angle  formed  by  the  roof  and  the  nasal  wall  of  the 
orbit.  From  this  pulley  its  direction  is  backward  and 
outward  and  passing  under  the  superior  rectus,  it  is 
inserted  into  the  outer  side  of  the  globe,  more  than  half 


ANATOMY    OK     IHl'.    lOYE.  5 

of  the  tendon  being  inserted  haek  of  the  e(|uat()r.  The 
inferior  obHque  runs  backward  and  outward,  and  ])ass- 
ing  between  the  orlntal  floor  and  the  inferior  rectus,  it 
is  inserted  into  the  outer  side  of  the  globe,  more  than 
half  of  the  tendon  being  back  of  the  equator  at  a  ])oint 
below  the  superior  oblique.  In  addition  to  its  scleral 
attachment,  some  fibers  from  the  superior  rectus  and 
its  sheath  pass  to  the  conjunctival  fornix  and  to  the 
to]i  of  the  tarsus,  bv  which  means  these  structures  are 


Fig.  4. — The  eye  muscles  seen  from  in  front. 

mo\'ed  in  harmony  with  the  upward  mo\'ement  of  the 
eyeball.  The  termination  of  the  inferior  rectus  is 
similar  to  that  of  the  superior.  In  the  same  way  fibrous 
bands  are  given  oft"  from  the  sheaths  of  the  internal  and 
external  recti  and  pass  laterally  to  the  bones  and  soft 
parts  of  each  side  of  the  orbit.  The  levator  palpebrcB 
siiperioris  muscle,  which  lifts  the  upper  lid,  owing  to 
its  location,  is  best  described  with  the  ocular  muscles. 


0  LESSONS    ON    THE   EYE. 

It  arises  at  the  apex  of  the  orljit  and  passes  forward  just 
under  the  roof  of  the  orbit  to  its  insertion  into  the  top  of 
the  superior  tarsus  by  a  fan-shaped  aponeurosis,  which 
is  as  broad  as  the  hd  itself.  The  motor  muscles  of 
the  eye  are  supplied  with  blood  by  the  muscular 
branches  of  the  ophthalmic  artery.  The  external  rectus 
muscle  is  supplied  by  the  sixth  nerve,  the  superior 
oblique  by  the  fourth  nerve,  and  the  four  remaining 
motor  muscles,  as  well  as  the  levator  palpebrae  superioris 
by  the  third  nerve. 

THE    LIDS. 

Under  the  skin  of  the  lids  is  a  thin  layer  of  connective 
tissue,  and  under  this  the  fibers  of  the  orbicularis  muscle. 
The  orbicularis,  which  closes  the  lids,  may  be  divided 
into  a  palpebral  part  which  lies  in  the  lids  proper  and  an 
orbital  portion  which  mingles  with  the  muscles  of  the 
forehead  and  cheek.  The  former  arises  from  the  inter- 
nal palpebral  ligament,  the  latter  from  the  bones  in 
front  of  the  lacrymal  groove.  The  tensor  tarsi,  or 
Horner's  muscle,  which  is  sometimes  considered  a  part 
of  the  orbicularis,  arises  from  the  lacrymal  bone  behind 
the  groove.  Both  of  these  muscles  are  supplied  by  the 
portio  dura  of  the  seventh  or  facial  nerve.  Under  the 
orbicularis  are  the  tarsi,  formerly  called  cartilage,  now 
known  to  be  dense  fibrous  tissue.  There  is  one  of  these 
thin,  flat,  elongated  plates  in  each  lid  to  give  it  form 
and  support,  the  tarsus  of  the  upper  lid  being  twice  as 
wide  as  the  tarsus  of  the  lower.  The  tarsi  are  connected 
at  their  extremities  and  also  bound  to  the  subjacent 
bone  by  the  internal  and  external  palpebral  ligaments. 


ANATOMY    OF    IHE    EYE. 


Fig.  5. — ^\'ertical  section  through  the  upper  eyelid.  A,  Cutis;  i,  epi- 
dermis; 2,  corium;  B  and  3,  subcutaneous  connective  tissue;  C  and  7,  orbic- 
ularis muscle;  D,  loose  submuscular  connective  tissue;  E,  insertion  of  H. 
Miiller's  muscle;  F,  tarsus;  G,  conjunctiva;  J,  inner,  K,  outer  edge  of  the 
lid;  4,  pigment  cells;  5,  sweat-glands;  6,  hair  follicles;  8  and  23,  sections  of 
nerves;  9,  arteries;  10,  veins;  11,  cilia;  12,  modified  sweat-glands;  13, 
circular  muscle  of  the  Riolan;  14,  Meibomian  gland;  15,  section  of  an  acinus 
of  the  same;  16,  posterior  tarsal  glands,  submuscular  connective  tissue; 
21  and  22,  conjunctiva,  with  its  epithelium;  24,  fat;  25,  loosely-woven 
pf)Steri()r  end  <if  the  tarsus;  26,  section  of  a  ])alpcbrai  artery.     (Schafcr.) 


5  LESSONS    ON    THE    EYE. 

These  ligaments  are  thickened  fibers  of  a  circular  fascia, 
the  septum  orbitale,  which  extends  from  the  rim  of  the 
orbit  to  the  orbital  edge  of  the  tarsi.  Under  the  tarsi 
and  in  grooves  in  their  substance  are  the  Meibomian 
glands.  They  number  about  thirty  in  the  upper  and 
twenty  in  the  lower  lid.  They  resemble  currants  on 
a  stem,  the  stem  lying  across  the  tarsus  and  at  right 


Fig.  6.— The  tarsi.     (Schwalbe.) 

angles  to  the  edge  of  the  lid.  Their  ducts  open  on  the 
free  margin  of  the  lid.  They  are  sebaceous  glands,  and 
the  fluid  they  secrete  prevents  adhesion  of  the  lid 
borders.  Under  the  Meibomian  glands  is  the  conjunc- 
tiva, the  mucous  membrane  which  covers  the  inner 
surface  of  the  lids.  The  opening  between  the  lids  is 
called  the  palpebral  fissure.  The  nasal  end  of  the  fissure 
is  the  inner  canthus,  the  temporal  end  is  the  outer  can- 
thus.  The  eyelashes  are  arranged  in  two  rows  and  their 
follicles  are  supplied  with  sebaceous  glands,  near  which 
are  found  the  glands  of  Moll,  usually  described  as 
modified  sweat  glands. 


LESSON  II. 

ANATOMY  OF  THE  EYE   (Contumcd) . 

THE    LACRYMAL    APPARATUS. 

The  lacrymal  apparatus  is  divided  into  the  secretory 
])art  and  the  excretory  part.  The  former  is  composed 
of:   I.  The  lacrymal  gland,  which  is  lodged  in  a  fossa 

at  the  up])er  and  outer  angle  of  the  orbit.     It  is  about 


Fig.  7. — Lacrymal  apparatus,  i,  Upper  lid;  2,  lower  lid;  3,  canaliculi; 
4,  lacrymal  sac;  5,  puncta;  6,  plica  semilunaris;  7,  caruncle;  8,  nasal  duct; 
g,  lacrymal  gland;  10,  tubules. 

the  size  of  the  kernel  of  an  almond,  and  the  fluid  it 
secretes  (tears)  empties  into  the  conjunctival  sac  near 
the  superior  temporal  fornix  through  small  tubes,  six 
to  ten  in   number.     2.  A   large  number  of  glandular 

9 


lO  LESSONS    ON    THE    EYE. 

lobules,  identical  in  structure  and  function  with  the 
lacrymal  gland,  imbedded  in  the  loose  connective 
tissue  of  the  conjunctival  fornix,  and  also  found  in  the 
tarsi  near  their  orbital  borders.  These  lobules  are 
largest  and  very  much  more  numerous  in  the  upper  lid 
at  the  external  canthws,  which  has  led  to  their  descrip- 
tion in  this  region  as  the  inferior  or  palpebral  lacrymal 
gland. 

The  excretory  apparatus  begins  with  the  four  mi- 
nute openings:  the  puncta,  one  of  which  is  located  on 
each  lid  border  about  a  quarter  of  an  inch  from  the 
inner  canthus.  The  puncta  open  into  small  tubes,  the 
canaliculi,  which  empty  by  a  common  orifice  into  the 
side  of  the  lacrymal  sac  at  a  point  just  behind  the 
internal  palpebral  ligament.  The  sac  extends  upward 
two  or  three  millimeters  above  the  internal  palpebral 
ligament  and  is  continuous  below  with  the  nasal  duct, 
which  empties  into  the  inferior  nasal  fossa.  The 
total  length  of  the  sac  and  duct  is  about  one  inch. 
Their  direction  is  a  little  backward  and  outward  from 
the  vertical. 

THE    CONJUNCTIVA. 

The  conjunctiva  is  a  mucous  membrane.  Its  ei)ithe- 
lial  layer  rests  upon  the  membrana  propria  which  is 
composed  of  white  fibrous  and  elastic  tissues.  The 
membrana  propria  is  united  to  the  underlying  struc- 
tures by  a  layer  of  submucous  connective  tissue.  There 
is  considerable  variation  in  the  histology  of  the  three 
parts  which  the  conjunctiva  presents  for  examination. 

I.  The  palpebral  conjunctiva  lines  the  inner  surface 
of  the  lids.     It  is  slightly  velvety,  due  to  numerous 


ANATOMY    OF    THK    KYK.  1  I 

fine  grooves  and  pits  in  its  surfaee;  the  elevations  be- 
tween the  grooves  are  called  papilla-.  The  membrana 
propria  is  closely  adherent  to  the  tarsus,  and  in  it  are 
said  to  be  found  numerous  lymphoid  follicles. 

2.  The  ocular  conjunctiva  covers  the  anterior  third 
of  the  eyeball  except  the  cornea.  Histologically  the 
outer  laver   of   the   cornea   is   simliar  in  structure    to 


Torni^  cart/unctiva^ 


CanfiiJictiMa.1 


juperiorH. 


Fig.  8. — Conjunctival  sac  (in  heavy  black,  exaggerated  for  sake  of  clearness.) 
(After  Merkel.) 


that  of  the  scleral  conjunctiva,  but  clinically  they 
appear  so  different  that  it  is  confusing  to  a  student 
to  describe  the  conjunctiva  as  covering  the  cornea. 
The  ocular  conjunctiva  is  very  loosely  connected  to 
the  underlying  tissues  except  at  the  circumference  of 
the  cornea  where  it  adheres  firmly.  On  the  ocular  con- 
junctiva, near  the  inner  canthus,  is  a  round,  fleshy 
body,  an  accumulation  of  glandular  follicles  called  the 
caruncle,  and  just  external  to  the  caruncle  is  the  plica 


12  LESSONS    ON    THE    EYE. 

semilunaris,  a  fold  of  the  conjunctiva  which  is  the 
analogue  of  the  third  eyelid  of  some  animals. 

3 .  The  ocular  and  palpebral  portions  above  described 
are  connected  by  a  loop  or  fold  of  mucous  membrane 
called  the  conjunctival /orw/.v.  In  the  fornix  are  located 
the  glandular  lobules  which  may  be  considered  acces- 
sory lacrymal  glands. 

In  the  conjunctiva  is  a  considerable  plexus  of 
lymphatic  vessels,  which  communicate  with  the  lymph 
spaces  of  the  cornea.  The  blood  supply  is  from 
branches  of  the  ophthalmic,  facial  and  internal  maxil- 
lary. The  sensory  ncr\'es  come  from  the  lacrymal  and 
nasal  branches  of  the  first  di\'ision  of  the  fifth  nerve. 


THE    EYEBALL. 

The  eyeball  is  a  globular  body  a  little  less  than  one 
inch  in  diameter.  It  is  not  quite  a  perfect  sphere,  as 
the  anterior  segment,  the  cornea,  has  a  greater  curva- 
ture than  the  rest  of  the  globe.  Anatomists  are  not 
agreed  as  to  which  diameter  is  the  longest. 

The  real  difference  in  the  size  of  the  eyes  of  individuals 
is  much  less  than  the  apparent  difference.  The  appar- 
ent difference  is  due  to  the  position  of  the  ball  in 
the  orbit,  whether  set  forward  or  far  back,  and  to  the 
shape  of  the  lids  and  the  width  of  the  palpebral  fissure. 
Normally  the  eye  should  be  so  ])laced  that  a  line  drawn 
from  the  upper  to  the  lower  orbital  margin  would 
just  touch  the  cornea. 

The  eyeball  consists  of  three  coats  or  tunics : 

I.  The  external,  fibrous  coat,  composed  of  the  sclera 
and  cornea. 


ANATOMY    Ol-     IHK    F.VK. 


2.  The  middle  coal,  called  the  u\eal  tract,  composed 
of  the  choroid,  ciliary  body,  and  iris. 

3.  The  nervous  coat,  the  retina. 


Fig.  9. — A  horizontal  section  of  the  eyeball.     (Deaver. 


The  interior  of  the  eye  is  divided  l)y  the  crystalline 
lens  into  the  aqueous  and  vitreous  chambers. 

The  aqueous  chamber  is  divided  by  the  iris  into  an 
anterior  and  posterior  chamber. 

The  following  terms  are  useful  for  descripti\-e  i)ur- 
poses : 


14 


LKSSONS    ON    THE    EYE. 


The  axis  of  the  eye  is  a  hne  drawn  from  the  eenter  of 
the  cornea,  through  the  center  of  the  ball  to  a  point  be- 


FiG.  lo. — Diagram  of  the  blood  vessels  of  the  eye.  (Horizontal  view; 
veins  black,  arteries  light,  w^ith  a  double  contour.)  aa,  Short  posterior  ciliary ; 
b,  long  posterior  ciliary;  cc',  anterior  ciliary  artery  and  vein;  dd',  artery  and 
vein  of  the  conjunctiva;  ee',  central  artery  and  vein  of  retina;  f,  blood 
vessels  of  the  inner,  and  g,  of  the  outer  optic  sheath;  h,  vorticose  vein;  i, 
posterior  short  ciliary  vein  confined  to  the  sclerotic;  k,  branch  of  the 
posterior  short  ciliary  artery  to  the  optic  nerve;  1,  anastomosis  of  the 
choroidal  vessels  with  those  of  the  optic  nerve;  m,  chorio-capillaris;  n, 
episcleral  branches;  o,  recurrent  choroidal  artery;  p,  great  circular  artery  of 
iris  (transverse  section);  q,  blood  vessels  of  the  iris;  r,  ciliary  process; 
s,  branch  of  a  vorticose  vein  from  the  ciliary  muscle;  u,  circular  vein;  v. 
marginal  loops  of  ve.ssels  on  the  cornea;  w,  anterior  artery  and  vein  of  the 
conjunctiva. 


ANATOMY    OF    TH  K    KVK.  15 

tvvecn  the  o})lic  iut\c  and  macula  liilca.  The  corneal 
end  of  this  line  is  the  anterior  pole,  the  other  end,  the 
posterior  pole  of  the  eye.  A  circle  around  the  ball  at 
an  equal  distance  from  the  poles  is  the  equator.  Other 
circles  around  the  hall,  ])assing  throui^h  the  ])oles.  arc 
meridians. 

THE    CORNEA. 

The  cornea  is  the  transparent,  glassy-looking,  circular 
membrane  which  forms  the  anterior  sixth  of  the  eye- 
ball. It  has  no  blood  vessels  except  the  capillary  loops 
which  encircle  its  periphery  and  encroach  upon  its 
substance  a  distance  of  about  one  millimeter.  The 
nutrition  of  the  cornea  is,  in  great  measure,  supi:)licd 
by  lymph  derived  from  this  capillary  system,  though 
the  deeper  layers  derive  some  nourishment  from  the 
fluid  of  the  anterior  chamber  by  osmosis.  The  nerve 
supply  is  from  the  fifth  and  is  very  profuse. 

The  cornea  has  five  layers: 

1.  In  front  a  layer  of  epithelium,  six  to  eight  cells 
deep,  which  is  continuous  with  and  similar  to  the  epithe- 
lium of  the  scleral  conjunctiva. 

2.  The  anterior  limiting  layer  or  membrane  of  Bow- 
man, a  homogeneous,  apparently  structureless,  resist- 
ing layer,  which  is  supposed  to  be  the  most  instrumental 
in  maintaining  the  normal  corneal  curve.  It  is  with 
difficulty  separated  from  the  substantia  propria. 

3.  Substantia  propria  or  proper  substance  of  the 
cornea,  a  transparent  fibrous  tissue,  not  as  dense  as  the 
preceding,  forming  the  greater  part  of  the  thickness  of 
the  cornea.  It  is  composed  of  about  sixty  layers,  the 
fibers  in  each  running  in  the  opposite  direction  to  the 


i6 


LESSONS    ON    THE    EYE. 


Fig.  II. — Section  of  rornea  near  the  limbus.  (Schafer.)  i,  Epithelium: 
2,  Bowman's  membrane;  3,  substantia  propria;  4,  Descemet's  membrane; 
5,  endothelium;  a,  oblique  fibers  in  the  anterior  layer  of  the  substantia 
propria;  b,  lamella;,  the  fibers  of  which  are  cut  across,  producing  a  dotted 
appearance;  c,  corneal  corpuscles  appearing  fusiform  in  section;  d,  lamella;, 
the  fibers  of  which  are  cut  longitudinally;  c,  transition  to  the  sclerotic,  with 
more  distinct  fibrillation,  and  surmounted  by  a  thicker  epithelium;  f,  Small 
l)lood  vessel  cut  across  near  the  margin  of  the  cornea. 


ANATOMY    OF    TIFF.    K\'V..  1 7 

fibers  in  the  layer  abo\-e  and  below.  Between  these 
layers  are  found  cell  spaces  which  communicate  with 
each  other  and  serve  as  lymph  channels.  Within  the 
cell  spaces  are  found  the  cor])uscles,  the  connective 
tissue  cells  of  the  cornea. 

4.  Posterior  limiting  layer  or  membrane  of  Descemet, 
a  thin,  homogeneous,  1  )rittlc  layer,  the  most  resisting  of 
the  cornea. 

5.  A  single  layer  of  endothelial  cells.  This  layer 
covers  the  ligamentum  pectinatum  at  the  angle  of  the 
anterior  chamber,  and  is  continued  over  the  anterior 
surface  of  the  iris. 


LESSON  III. 

ANATOMY  OF  THE  EYE  {Continued). 

THE    SCLERA. 

The  sclera  composes  five-sixths  of  the  outer  tunic  of 
the  eyeball.  It  is  made  of  white  fibrous  and  yellow 
elastic  tissue  with  some  pigment  in  its  deeper  layers. 
It  is  essentially  of  the  same  constituents  as  the  cornea, 
but  its  tissues  are  so  arranged  as  to  almost  wholly 
intercept  rays  of  light.  Though  the  sclera  is  tough  and 
resisting,  the  form  of  the  eye  is  not  maintained  by  it, 
as  it  will  collapse  if  the  contents  of  the  ball  escape. 

The  sclera  is  covered  by  a  thin  layer  of  loose  con- 
nective tissue  called  the  episdera.  The  optic  nerve 
passes  through  the  sclera  at  a  point  about  3  millimeters 
toward  the  nasal  side  and  i  millimeter  below  the 
])osterior  pole  of  the  ball.  It  does  not  enter  in  one 
bundle  but  divides  and  passes  through  numerous 
openings.  This  sieve-like  part  of  the  sclera  is  called 
the  lamina  cribrosa.  Around  the  lamina  cribrosa  the 
numerous  posterior  ciliary  vessels  and  ner\'es  pierce  the 
sclera.  Behind  the  equator  the  4  to  6  venas  vorticosae 
find  their  exit,  and  about  2  millimeters  from  the  cornea 
the  5  to  8  anterior  ciliary  arteries  pass  in  to  their 
distribution  to  the  iris  and  ciliary  body.  The  sclera 
and  underlying  choroid  are  connected  by  a  \erv  loose, 
pigmented  connectixe  tissue  whose  meshes  com- 
t8 


ANATOMY    OV    THE    EYE.  I  (; 

municate  so  as  to  form  a  lymph  space :  the  perichuroidal. 
If  the  sclera  is  separated  from  the  choroid  half  of  the 
brown,  pigmented  connective  tissue  adheres  to  the 
sclera  forming  its  inner  layer,  called  the  lamina  fusca. 
The  contents  of  the  perichoroidal  space  escaj^e  through 
lymph  channels  which  are  found  around  the  vessels  and 
nerves  that  pierce  the  sclera.  The  sclera  is  poorly 
supplied  with  blood  vessels,  its  nourishment  coming 
mostly  from  the  lymph  of  the  perichoroidal  and  peri- 
scleral  spaces.  Completely  encircling  the  cornea,  but 
lying  in  the  scleral  tissue,  is  found  the  canal  of  Schlemm. 
There  is  yet  a  division  of  opinion  as  to  whether  it  is  a 
venous  or  lymphatic  channel.  That  it  is  instrumental 
in  draining  the  anterior  chamber  is  generally  accepted. 

THE    IRIS. 

From  a  point  corresponding  to  the  internal  junction 
of  the  cornea  and  sclera  a  curtain  is  suspended  in  the 
aqueous  chamber.  This  curtain,  the  iris,  is  the  most 
anterior  portion  of  the  uveal  tract  or  vascular  coat  of 
the  eye.  It  is  composed  of  muscular  fibers,  pigment, 
blood  vessels,  nerves,  and  connective  tissue.  The 
amount  of  pigment  in  the  iris  determines  its  color, 
which  may  vary  from  the  pink  of  an  albino  to  the 
deep  brown  of  a  negro.  In  the  center  of  the  iris  is  a 
round  opening:  the  pupil.  The  muscular  fibers  of  the 
iris  are  involuntary  (unstriped)  and  are  divided  into 
radiating  and  circular  fibers.  The  latter  are  arranged 
around  the  pupil  and  act  as  a  sphincter  in  contracting 
it.  These  fibers  are  controlled  by  the  third  nerve. 
The    radiating    fibers   whose  esistence    is    doubted    bv 


20  J.ESSONS    ON    THE    EYE. 

some,  are  supposed  to  dilate  the  pupil  and  are  con- 
trolled by  the  sympathetic  nerve.  The  function  of 
the  iris  is  to  regulate  the  amount  of  light  entering 
the  eye.  In  accomplishing  this  its  action  is  reflex, 
the  afferent  nerve  being  the  optic,  the  efferent  nerve 
the  third.     In  front  of  the  iris  and  between  it  and  the 


Fig.  12. — Arteries  of  the  iris.  (Sappc}'.)  i,  i,  Long  posterior  ciiiar)- 
arteries;  2,  3,  their  branches  of  bifurcation;  4,  recurrent  arteries  destined  for 
the  choroid;  5,  5,  6,  6,  anterior  ciliary  arteries  anastomosing  with  the  long 
ciliary  to  form  tlie  greater  arterial  circle  of  the  iris;  7,  the  lesser  arterial  circle 
of  the  iris. 


cornea  is  the  aiiicn'or  chanibcr.  The  region  of  the 
anterior  chamber  where  the  cornea  and  iris  unite  is 
called  the  angle  of  the  anterior  chamber.  In  the 
angle  of  the  anterior  chaml)er  is  found  the  pcctiiialc 
ligament,  composed  of  interlacing  tral)ecuke,  which 
extend  fnjm  Descemet's  membrane  of  the  cornea  to  the 
iris.     The    si)onge-like    framework    of    the    i)eciinate 


ANATOMY    OF     IlIE    EYE. 


ligament  incloses  numerous  intercommunicating  spaces : 
the  spaces  of  Fontana.  The  fluid  in  the  anterior  cham- 
ber drains  through  the  spaces  of  Fontana  into  the 
canal    of    Schlemm    (page    174).      It    is   also    claimed 


3--  ^f^  M  fin  i 


Fig.  13. — Section  of  ciliary  body  and  iris,  i,  i,  Ciliarj-  processes;  2,  2. 
their  base  or  rounded  extremity;  3,  3,  their  apex;  4,  a  process  with  bifur- 
cated extremity;  5,  5,  reticulated  folds,  or  ciliary  process  of  the  second  order; 
6,  6,  venules  that  emanate  from  these;  7,  7,  ora  serrata  of  choroid;  8,  8. 
veins  of  choroid;  9,  section  of  iris;  10,  10,  circumference  of  iris;  11,  11, 
small  ring  of  iris;  12,  12,  large  ring  of  iris. 


that  the  aqueous  fluid  is  absorbed  in  part  by  the 
surface  of  the  iris.  Behind  the  iris  is  the  posterior 
chamber.  Viewed  laterally  (meridional  section),  the 
posterior  chamber  is  triangular  in  shape.  The  base 
of  the  triangle  is  the  ciliary  body;  the  two  sides,  the 
iris  and  lens;  the  apex,  the  point  where  the  pupillary 


2  2  LESSONS    OX    THE    EYE. 

mcirgin  of  the  iris  comes  in  contact  with  the  lens. 
The  anterior  and  ])osterior  chamljcrs  form  the  aqueous 
chamber.  The  long  ciliary  arteries,  two  in  number, 
arise  from  the  ophthalmic  and  pierce  the  sclera,  one  on 
each  side  of  the  optic  nerve.  They  pass  forward 
between  the  choroid  and  sclera  to  the  periphery  of  the 
iris,  where  they  divide  into  an  ascending  and  descending 
branch.  The  six  to  eight  anterior  ciliary  arteries  are 
derived  from  either  the  muscular  or  lacrymal  branches 
of  the  ophthalmic  and  pierce  the  sclera  near  the 
corneal  junction.  They  anastomose  with  the  branches 
of  the  long  ciliary  to  form  the  cir cuius  arteriosus  iridis 
major,  from  which  branches  radiate  toward  the  pupil 
and  around  its  margin  from  the  circulus  arteriosus 
iridis  minor  (Fig.  12). 

THE    CILIARY    BODY. 

The  ciliary  body  lies  between  the  iris  and  the  anterior 
end  of  the  retina.  It  is  firmly  adherent  to  the  sclera 
at  the  anterior  end  but  loosely  attached  behind.  It  is 
divided  into  two  parts : 

1 .  The  vascular  part,  which  is  composed  of  convoluted 
blood  vessels,  connective  tissue,  and  pigment,  lies  next 
to  the  vitreous  and  supplies  it  and  the  lens  with  much 
of  their  nourishment.  It  is  also  supposed  to  be  the 
principal  agent  in  the  secretion  of  the  aqueous  humor. 
The  anterior  part  of  the  vascular  portion  is  thrown  into 
seventy  or  eighty  projecting  tips,  the  ciliary  processes. 

2.  The  muscular  part  lies  next  to  the  sclera  and  is  the 
agent  of  accommodation.  Its  fibers  are  unstriped  and 
are  arranged  in  two  sets.     Those  nearest  to  the  sclera 


ANATOMY    OF    THE    EYE. 


23 


Fig.  14. — Section  through  the  ciliary  region.  (Fuchs.)  C,  cornea;  S, 
sclera;  Ch,  choroid;  R,  retina;  Pe,  its  pigmented  epithelium;  o,  orra  serrata; 
O,  pars  ciliaris  retinae;  this  is  continued  over  the  ciliary  processes;  pe,  pet, 
pigmented  and  non-pigmented  cells  of  pars  ciliaris;  D,  lens;  M,  ciliary  muscle; 
r,  its  radiating  fibers;  Mu,  circular  fibers;  ci,  anterior  ciliary  artery;  S,  canal 
of  Schlemm;  z,  origin  of  ciliary  muscle;  c,  c,  f,  f,  folds  and  depressions  in 
anterior  surface  of  iris;  cr,  a  crevice  in  this  surface  (?  artificial);  sp,  sphincter 
pupillas;  p,  edge  of  pupil;  P,  most  prominent  part  of  ciliary  process;  h,  pig- 
ment behind  iris,  detached  at  v;  a,  blood  vessel;  z,  zonula  of  Zinn;  z',  z',  its 
continuation  or  the  suspensory  ligament;  i,  i,  spaces  between  the  fibers  of  the 
suspensory  ligaments;  k,  capsule  of  lens. 


24 


LESSONS    ON    THE    EYE. 


run  meridionally  and  those  next  to  the  iris  equatorially. 
Contraction  of  the  cihary  muscle  is  produced  by  those 
fibers  of  the  cihary  ner\'es  which  are  derived  from  the 
third.  The  long  ciliary  nerves,  two  or  three  in  number, 
are  given  off  from  the  nasal  nerve  which  is  a  branch 
of  the  ophthalmic;  the  ophthalmic  being  the  first 
division  of  the  trigeminus  or  fifth.     The  short  ciliary 


Sclerotic 
coat. 
Veins  of   the 
choroid. 


Ciliary 
nerves. 


Veins  of   the 
choroid. 


_       Ciliary  body. 


Fig.  15. — Sclerotic  coat  removed  to  show  the  choroid 
nerves. 


iliarv  muscle,  and 


nerves,  ten  or  twelve  in  number,  arise  from  the  ciliary 
or  lenticular  ganglion.  ■  This  ganglion,  which  is  about 
the  size  of  a  pin  head,  is  found  back  of  the  globe 
between  the  optic  nerve  and  external  rectus  muscle. 
It  is  supplied  by  three  roots  from  the  fifth,  third,  and 
sympathetic  nerves.  The  long  and  short  ciliary  nerves 
pierce  the  sclera  around  the  optic  nerve  and  pass 
forward  between  the  choroid  and  the  sclera  to  the 
ciliary  muscle  and  iris  (Fig.  15). 


ANATOMY    OF    THE    EYE. 


25 


THE    CHOROID. 

Extending  from  the  ciliary  body  back  to  the  optic 
nerve  and  lying  next  to  the  sclera  is  a  vascular  mem- 
brane, the  choroid.  It  is  connected  to  the  sclera  by 
the  loose  fibrous  trabeculrc  described  on  page  18. 
It  has  four  layers. 


^~^ 


(   Sclerotic 


■Lam.  supni-clioroidea. 


Layer  of  large  vessels. 


Limiting  layer. 
-;- — .  ( 'liorio-capillaris. 

Hyaline  membrane. 


"Pigment  layer  of  retinju 
Fig.  16. — ^\''ertical  section  of  the  choroid  and  a  part  of  the  sclerotic,     g,  Large 
blood  vessels;  p,  pigment  cells;  c,  section  of  capillaries. 


I..  When  the  sclera  and  choroid  are  torn  apart  half  of 
this  fiuffy,  pigmented  membrane  adheres  to  the  sclera 
(lamina  fusca)  and  half  to  the  choroid.  The  part 
adhering  to  the  choroid  is  called  the  suprachoroidea . 
It  is  reddish-brown  in  color;  due  to  the  presence  of 
numerous, stellate,  pigmented  cells. 


26 


LESSONS    ON    THE    EYE. 


2.  UndtT  llu'  siiprachoroidca  is  found  the  Luniiia 
vasculosa,  a  layer  of  arteries  and  veins  held  together  by 
connective  tissue.     There  are  also  some  stellate  pig- 


FiG.  17. — Circulation  of  the  choroid  (Leber.)  O,  Optic  nerve  entrance; 
Oc,  ciliary  region;  Pc,  ciliary  processes;  J,  iris;  Aa,  anterior  ciliary  arteries; 
Ab,  short  posterior  ciliary  arteries;  .'\1,  long  posterior  ciliary;  Cim,  circulus 
arteriosus  iridis  major;  Mc,  arteries  of  ciliary  muscle;  Vv,  vena  vortirosa. 


ment  cells  in  this  layer.  The  arteries  are  derived  from 
the  twelve  to  twenty  short  posterior  ciliary,  which 
arise  from  the  ophthalmic  and  pass  through  the  sclera 
around    the    ()])tic    nerxx'.     Some    recurrent    branches 


ANATOMY    OF    'raE    EYE.  27 

from  llu'  lonj;-  ciliary  and  the  anterior  ciliary  arteries 
enter  into  the  anterior  portion  of  the  lamina  vasculosa. 

3.  The  arteries  divide  and  anastomose  to  form  a 
capillary  layer  under  the  lamina  vasculosa  called  the 
chorio-capillaris.  The  chorio-capillaris  helps  to  nour- 
ish the  retina  and  vitreous.  The  veins  of  the  choroid 
arise  from  the  chorio-capillaris  and  form  the  ciliary 
body  and  iris  and  unite  into  four  or  six  groups.  Each 
group  empties  near  the  equator  through  one  vein,  the 
vena  vorticosa.  The  ven^e  vorticos^e  empty  into  the 
ophthalmic  vein. 

4.  Under  the  chorio-capillaris  and  firmly  united  to 
it  is  found  the  innermost  layer,  the  lamina  basilis. 
It  is  a  thin  transparent  layer  of  condensed  connective 
tissue. 


LESSON  IV. 

ANATOMY  OF  THE  EYE  {Continued). 

THE    LENS. 

Behind  the  iris  and  in  contact  with  its  pupillary 
margin  lies  the  crystalline  lens,  a  circular,  biconvex, 
transparent  body,  composed  largely  of  albumen  and 
water.     Its  posterior  surface  fits  into  the  hyaloid  fossa 


Fic.  1 8. —Meridional  section  thnnif^h  the  crystalline  lens.      (Hahuchin.) 

of  the  vitreous.  The  cur\-ature  of  the  posterior  surface 
is  much  greater  than  that  of  the  anterior.  The  lens  is 
contained  in  a  trans])arent  ca])sule,  named  according 

2S 


ANAIOMV    (IF    THK    F.YE.  29 

to  location  the  anterior  and  posterior  capsules.  The 
peripheral  edge,  or  the  point  of  union  between  the 
anterior  and  i)osterior  capsules,  is  called  the  equator  of 
the  lens. 

The  lens  is  held  in  position  l)y  the  suspensory  liga- 
ment, or  zonula  of  Zinn,  which  is  composed  of  delicate 
fibers  that  arise  from  the  posterior  surface  of  the  ciliary 
processes.  These  fibers  are  inserted  into  the  equatorial 
region,  some  going  to  the  anterior  and  some  to  the 
posterior  capsule.  The  lens  is  divided  into  a  dense 
central  part,  the  nucleus,  and  a  softer  peripheral  part, 
the  cortex.  There  Ts  no  abrupt  transition  between  these 
parts,  there  being  a  gradual  centrifugal  increase  in  the 
density  of  the  lens  as  age  advances. 

THE    VITREOUS. 

The  interior  of  the  eyeball,  back  of  the  lens,  is 
tilled  by  a  transparent,  jelly-like  connective  tissue, 
the  vitreous,  which  maintains  the  shape  of  the  eye,  and 
holds  the  retina  and  lens  in  position.  It  has  no  blood 
\'essels  or  ner\-es  and  is  nourished  by  lymph  from  the 
vessels  of  the  ciliary  body,  retina,  and  choroid.  Through 
its  center  from  the  optic  disc  to  the  center  of  the 
posterior  surface  of  the  lens,  runs  the  hyaloid  canal,  or 
canal  of  Cloquet,  a  lymph  channel,  which  is  supposed 
to  communicate  in  front  with  the  aqueous  humor  and 
behind  with  the  lymph  sj^aces  surrounding  the  optic 
nerve.  In  fetal  life  it  contains  the  hyaloid  artery.  The 
\-itreous  is  contained  within  a  thin  capsule,  the  hyaloid 
membrane.  Anteriorly  the  vitreous  presents  the  hyaloid 
fossa  into  which  the  posterior  surface  of  the  lens  fits. 


30  LESSONS    ON    'mE    EYE. 


THE    RETIXA. 


The  fibers  of  the  optic  nerve  pass  through  the  lamina 
cribrosa  and  spread  between  the  choroid  and  vitreous, 
forming  an  almost  transparent  membrane,  the  retina. 
It  extends  forward  to  a  point  corresponding  with  the 
union  of  the  choroid  and  ciliary  body,  terminating  in  a 
wavy  line  called  the  ora  serrata.  It  is  composed  of  ten 
layers,  the  most  external  or  one  lying  next  to  the 
choroid,  being  a  pigment  layer  which  does  not  terminate 
at  the  ora  serrata  but  continues  over  the  ciliary  body 
and  posterior  surface  of  the  iris  to 'the  margin  of  the 
pupil. 

The  other  nine  layers  are  composed  of  very  com- 
plicated nerve  structures  and  their  supporting  con- 
nective tissue.  In  the  center  of  the  retina  is  a  round 
area  about  one-twentieth  of  an  inch  in  diameter,  the 
macula  lutea,  so  called  from  the  yellow  color  it  assumes 
soon  after  death.  In  the  center  of  the  macula  is  a 
slight  depression  which  appears  as  a  more  deeply  colored 
point  or  spot.  This  spot,  which  corresponds  to  the 
posterior  end  of  the  visual  axis,  is  called  the  fovea 
centralis.  It  is  the  center  of  direct  vision  and  the  most 
sensitive  part  of  the  retina.  A  little  toward  the  nasal 
side  of  the  retina  is  seen  the  large,  circular  white  spot, 
the  optic  disc  or  intra-ocular  end  of  the  optic  nerve. 
The  arteria  centralis  retinae  pierces  the  optic  nerve  i .  5 
centimeters  from  the  eyeball  and  passes  forward 
through  its  center  to  the  optic  disc  where  it  divides  into 
its  branches,  which  spread  out  in  all  directions  in  the 
retina.  There  is  no  anastomosis  between  the  retinal 
arteries,  hence  an  obstruction  of  one  of  tlicni  rt'sults 


ANATOMY    OF    THK    EYK 


3^ 


in  destruction  of  the  area  which  it  nourishes.  The 
retinal  veins  he  by  the  side  of  the  arteries.  The  retina 
is  attached  to  the  underlying  structures  only  at  the 
optic  disc  and  at  the  ora  serrata.  vShrinkage  of  the 
\'itreous  is  prone  to  cause  separation  of  the  retina  from 
the  choroid  anywhere  between  these  two  points. 


Fig.  19. — Section  through  ojitic  nerve  and  jKipiUa.      (.\fter  Flemniing.) 


THE    OPTIC    NERVES. 

An  optic  nerve  may  be  divided  into  three  parts: 
I.   Intra-ocular.     2.  Orbital.     3.   Intra-cranial. 

I.  The  optic  nerve  fibers  pass  through  the  sclera  at 
the  lamina  cribrosa  and  then  radiate  in  every  direction 
to  form  the  retina.  That  portion  of  the  nerve  between 
the  lamina  cribrosa  and  the  point  where  it  disperses  to 
form  the  retina  is  called  the  head  of  the  nerve,  the  optic 
disc   or   optic    pai)illa.     With    the    o])hthalmoscope    it 


32  LESSONS    ON    THE    EYE. 

shows  as  a  round  white  sj^ot  almost  in  the  center  of  the 
posterior  wall  of  the  eye.     (See  colored  plate.) 

2.  The  orbital  portion  of  the  optic  nerve  extends 
from  the  sclera  to  the  optic  foramen.  It  curves  in  the 
shape  of  an  S,  which  enables  the  eye  to  move  freely  in 
all  directions  without  subjecting  the  nerve  to  undue 


,|£f 


Fig.  20. — Optic  tracts  and  commissure. 

tension.  The  nerve  fibers,  about  half  a  million  in 
number,  are  collected  into  numerous  bundles  which 
are  inclosed  in  a  framework  of  connective  tissue.  The 
sheaths  of  the  optic  nerve  are  three  in  number,  the 
dura,  arachnoid,  and  pia  mater,  which  originate  from 
the  same  membranes  of  the  brain.  Under  the  dural 
sheath  is  a  lymph  space:  the  sul)(lural,  and  under  the 


ANATOMY    Ol'     llll';     F-.N  !■:.  ^3 

arachnoid  another:  the  sub-arachnoid  spaci'.  These 
spaces  communicate  with  the  cerebral  s])aces  of  the 
same  name.  Anteriorly,  the  three  sheaths  merge  into 
the  sclera. 

3 .  The  intra-cranial  portion  of  an  optic  nerve  extends 
from  the  optic  foramen  to  the  chiasm,  a  distance  of  less 
than  one  centiineter.      In  this  res/ion  it  has  lost  its  two 


Left 


Fig.  21. — Decussation  of  tin-  ojjtic    lUMve 


outer  sheaths  which  ha\e  merged  into  the  correspond- 
ing membranes  of  the  brain.  Though  the  optic  nerves 
proper  end  at  the  chiasm,  their  fil)ers  are  conveyed 
from  the  chiasm  to  their  termination  in  the  brain  by  two 
nerve  bundles  called  the  optic  tracts.  \n  the  chiasm 
or  optic  commissure,  which  lies  in  the  optic  groove  of 
the  body  of  the  sphenoid  bone,  a  jjartial  decussation  of 
the  optic  nerve  fibers  takes  ])lace.  The  fibers  from 
the  nasal  side  of  each  retina  cross  to  the  optic  tract 
of  the  opposite  side.  The  fibers  from  the  temporal  side 
of  each  retina  pass  back  to  the  brain  without  decussa- 


34  LESSONS    ON    THK    EYE. 

lion.  Thus  it  will  be  seen  that  the  right  ojjtie  tract 
is  made  up  of  the  fibers  which  supply  the  right  side  of 
each  retina  and  the  left  optic  tract  the  fibers  of  the  left 
side  of  each  retina  (Fig.  21).  The  principal  termina- 
tion of  the  optic  tracts  is  in  the  cuneus  of  the  occipital 
lobe.  A  small  bundle  is  sent  to  the  nucleus  of  the 
third  nerve. 


LESSON  V. 

OPTICS. 


Light  is  emitted  from  every  point  of  a  luminous  body, 
in  successive  waves,  like  the  circles  which  form  when 
a  stone  is  dropped  in  still  water.  The  number  of  waves 
per  second,  and  consequently  the  waves  lengths,  vary 
with  the  nature  of  the  luminous  body. 

A  line  from  a  luminous  point,  perpendicular  to  a 
wave  front  represents  a  ray  of  light.  It  is  the  smallest 
sub-division  of  light  traveling  in  a  straight  line  (Fig.  22) . 


Fig.  22. — The  circles  represent  the  light  waves  emitted  from  the  candle 
A.  AB,  AC,  and  AD  perpendicular  to  the  wave  fronts  represent  rays  of 
light  from  the  candle  A. 

The  velocity  of  a  ray  of  light  is  less  in  a  dense  than  in 
a  rare  medium.  All  transparent  solids  and  liquids  are 
denser  than  air.  This  change  in  the  velocity  of  light 
through  different  media  causes  refraction  (Fig.  23). 

Refraction  is  the  change  which  takes  place  in  the 

direction  of  rays  of  light  when  they  pass  obliquely  from 

one   transparent    medium    into    another    of   different 

density.     Rays  which  pass  into  the  second  medium 

35 


LESSONS    ON    THE    EYE. 

»        D  E 


Fig.  23. — AB  represents  a  ray  of  light  passing  through  a  rectangle  of  glass 
D  E  C  F.  The  parallel  cross  lines  represent  the  series  of  wave  fronts  by 
which  the  ray  is  propagated.  These  wave  fronts  are  such  small  arcs  of  a 
circle  that  they  may  be  regarded  as  straight  lines.  Every  part  of  a  wave 
moves  with  equal  velocity  while  in  the  same  medium.  The  point  i  of  the  wave 
I,  2,  enters  the  glass  first  and  its  velocity  lessens  while  the  velocity  of  the  point 
2  remains  the  same.  The  result  is  that  point  2  will  reach  point  4  while  point 
I  is  going  to  point  3  and  the  direction  of  the  wave  front  is  changed.  Since 
the  ray  is  perpendicular  to  the  wave  fronts  its  direction  is  also  altered.  The 
same  theory  will  explain  the  change  in  the  direction  of  the  ray  upon  emerging 
from  the  surface  D  C. 


Fig.  24. — AA,  perpendicular  to  surface  between  air  and  glass.  C  B  1), 
ray  bent  toward  perpendicular  when  passing  from  rarer  medium  air  into 
denser  medium  glass.  Reverse  the  directi-.jn  and  D  B  C  is  a  ray  bent  from 
the  perpendicular  when  passing  from  the  denser  medium  glass  into  the  rarer 
medium  air. 


OPTICS.  37 

perpendicular  to   its   surface   are   not   deviated    (a   a, 
Fig.  24). 

A  ray  of  light  passing  from  a  rarer  into  a  denser 
medium  is  bent  toward  the  perpendicular.  A  ray  of 
light  [massing  from  a  denser  into  a  rarer  medium  is  l)ent 

A 


Fig.  25. — A  A  .\,  a  prism;  B  B  B,  perpendiculars  to  sides  of  prism;  i,  2, 
3,  ray  bent  toward  perpendicular  when  passing  from  air  into  glass;  2,  3,  4, 
ray  bent  from  perpendicular  when  passing  from  glass  into  air. 

from  the  perpendicular  (Fig.  24).  The  degree  of  the 
deviation  depends  upon  the  difference  in  the  density 
of  the  two  media. 

From  Fig.  23  we  can  also  learn  why  a  ray  which  passes 
perpendicularly  from  one  medium  into  another  of  dif- 


FiG.  26. — The  incident  ray  i,  2,  is  perpendicular  to  the  surface  A  B.  It  is 
not  refracted  until  it  reaches  the  surface  A  C,  when  it  is  bent  toward  the 
base  B  C. 

ferent  density  is  not  refracted.  If  the  ray  is  perpen- 
dicular to  the  surface  of  the  second  medium  the  wave 
fronts  will  be  parallel  with  this  surface  and  every  part 
of  the  wave  fronts  will  strike  the  second  medium  at  the 
same  time.  Though  the  velocity  of  the  ray  will  be 
altered  the  direction  will  be  the  same. 


38 


LESSONS    ON    THE    EYE. 


A  refracting  prism  is  any  transparent  body  lying 
between  two  plane  faces  which  are  not  parallel.  The 
apex,  sides,  and  base  of  a  prism  are  terms  which  explain 
themselves.  The  refracting  angle  is  formed  by  the 
apex  and  the  two  sides.  A  ray  of  light  upon  entering  a 
prism  is  bent  toward  the  perpendicular,  upon  emerging 


Fig. 


-The  image  of  the  candle  B  is  displaced  toward  the  ape.x  of  the 
prism  and  is  seen  at  A. 


it  is  bent  from  the  perpendicular.     A  prism  always 
bends  rays  toward  its  base  (Fig.  25). 

If  an  incident  ray  is  perpendicular  to  the  side  of  a 
prism  it  will  not  be  refracted  until  it  emerges  from  the 
other  side  (Fig.  26). 


Fig.  28.  Fig.  29. 

The  image  of  an  object  seen  through  a  prism  is  dis- 
])laced  toward  the  apex  of  the  prism  (Fig.  27). 

Formerly  prisms  were  numbered  by  the  degrees  of 
their  refracting  angles.  Now  the  centrad  of  Dennett 
and  the  i)rism-diopter  of  Prentice  are  more  or  less  com- 


OPTICS. 


39 


plicated  methods  in  \-ogue.  The  difference  in  the 
results  obtained  by  the  three  methods  of  computation 
are  not  sufficiently  vital  to  warrant  their  explanation 
here. 


Fig.  ,:;o.— The  line  A  through  the  center  of  the  lens  represents  the  |)nn(i]j;il 
axis;  P  F,  the  [jrincipal  focus. 

A  lens  is  any  transparent  medium  bounded  by  two 
curved  surfaces  or  one  plane  and  the  other  cur\-ed. 
Lenses  are  divided  into  spheric  and  cylindric. 

A  curved  surface  of  a  spheric  lens  is  the  section  of  a 
sphere,  hence  the  name.  Spheric  lenses  are  either 
convex  or  concave. 


Fig.  31. — P  F,  principal  focus;  A  B  are  conjugal 


A  convex  lens  may  be  regarded  as  a  series  of  prisms 
with  their  bases  directed  toward  the  center  (Fig.  28). 
The  strength  of  these  prisms  increases  from  the  center 
toward  the  periphery  in  such  proportion  as  to  bend  all 
parallel  rays  passing  through  them  to  a  common  ])oinl. 

A  straight  line,  perpendicular  to  both  surfaces  of  a 
lens,   and  passing  through  its  center  of  curwiture  is 


40 


LESSONS    ON    THE    EYE. 


called  its  principal  axis.  All  rays  of  light  parallel  with 
the  principal  axis  are  brought  to  a  focus  at  a  point  on 
the  principal  axis.  This  point  is  called  the  principal 
focus.     The  distance  from  the  0]:)tical  center  of  a  con- 


rf: 


Fig. 


-P  F,  principal  focus.     Rays  from  the  point  B  l^etween  the  lens 
and  its  principal  focus  are  rendered  divergent. 


vex  lens  to  its  principal  focus  is  called  its  focal  distance. 
Rays  which  di\'erge  from  the  principal  focus  and  pass 
through  a  convex  lens  are  rendered  parallel  (Fig.  30) . 
Rays  which  diverge  from  a  point  farther  than  the 


principal  focus  and  pass  through  a  con\-ex  lens  are 
brought  to  a  focus  again.  The  two  points  on  the 
axial  ray  where  these  rays  come  together  are  called  con- 
jugate foci  (Fig.  31). 

Rays  which   di\'crgc  from  a   ])()int   nearer  than   the 


OPTICS. 


41 


])rincipal  focus  remain  (li\ci\^cnt  after  i)assing  throuj^^h 
a  convex  lens  (Fig.  32). 

A  concave  lens  may  be  regarded  as  a  series  of  jjrisms 
with  their  l)ases  directed  away  from  the  center  (Fig.  33) . 


Fic.  ,-;5. — The  lim-  A  ihrough  the  center  of  the  lens  represents  the  principal 
axis.     P  F,  the  principal  focus  which  is  negative  or  virtual. 

the  strength  of  these  prisms  increasing  from  the  center 
toward  the  periphery. 

All   rays   of   light   passing  through   a   concave   lens 
parallel  with  the  axial  ray  are  rendered  divergent.     1/ 


Fig  36. — Different  forms  of  spheric  lenses,  i,  Biconvex  lens;  2,  planocon- 
vex lens;  3,  concavoconvex,  or  convergent  meniscus;  4,  biconcave;  5,  plano- 
concave; 6,  convexoconcave,  or  divergent  meniscus. 

these  divergent  rays  be  projected  backward  in  a  straight 
line,  they  will  come  to  a  negative  or  virtual  focus  at  a 
point  on  the  axial  ray  (Fig.  35).  The  distance  from 
this  point  to  the  optical  center  of  the  lens  is  its  focal 


42 


LESSONS    ON    THE   EYE. 


distance.  As  a  concave  lens  always  diverges  rays, 
regardless  of  the  distance  from  whence  they  come,  its 
focus  is  always  negative. 

There  are  three  forms  of  convex  lenses :  planoconvex, 
biconvex,  and  concavoconvex ;  also  three  forms  of  con- 
cave lenses:  planoconcave,  biconcave,  and  convexo- 
concave  (Fig.  36). 

Convex  lenses  are  designated  +  (plus) ;  concave 
lenses  -  (minus). 


Fig.  T,y. — A,  B,  C,  T)  is  ;i  section  of  a  cylinder  cut  parallel  to  its  a.\is 


A  cylindric  lens  derives  its  name  from  the  fact  that  it 
is  the  section  of  a  cylinder  (Fig.  3  7) .  The  section  is  cut 
parallel  with  the  axis  of  the  cylinder.  The  rays  which 
pass  through  the  axis  are  not  refracted  since  there  is  no 
curvature  in  this  direction.  Rays  passing  through 
the  meridian  which  is  perpendicular  to  the  axis  undergo 
the  maximum  amount  of  refraction,  since  the  lens 
presents  its  greatest  degree  of  cur\-ature  in  this  direc- 
tion.    The    refracting    value    of    any    meridian    lying 


OPTICS. 


43 


between  these  two  ])riiieipal  meridians  depends  ui)c)n 
its  proximity  to  the  region  of  no  refraction  (the  axis), 
or  to  the  region  of  maximum  refraction  (Fig.  38). 


Fig.  38. — A  lens  cut  from  a  section  of  a  cylinder.  The  meridian  i,  2,  is 
parallel  to  the  axis  of  the  cylinder;  it  has  no  curvature  and  no  refracting  power. 
The  meridian,  3,  4,  being  thicker  at  the  middle  than  at  the  ends,  is  conve.x; 
it  will  bring  parallel  rays  of  light  to  a  focus. 

Cyhndric  lenses  may  be  convex  or  concave  (Figs.  39 
and  40).  They  are  designated  by  the  abbreviation  C, 
or  cyl. 


Fig.  39. — A  convex  cylinder.     Fig.  40. — .\ 


linder. 


The  strength  of  a  lens  or  its  ability  to  change  the 
direction  of  rays  depends  upon  the  density  of  the 
material  of  which  it  is  made  and  the  degree  of  curvature 
of  its  surfaces. 


44  LESSONS    ON    THE    EYE. 

The  greater  the  strength  of  a  lens  the  shorter  is  its 
focal  distance.  The  term  diopter  is  used  in  numbering 
lenses.  A  lens  whose  focal  distance  is  one  meter  is 
called  a  one  diopter  lens,  or  i.D.  A  lens  of  two  meters' 
focus  has  only  one-half  the  refractive  power  of  a  i.D 
lens  and  is  called  a  half  diopter  lens,  or  0.50  D.  If 
the  focal  distance  is  one-quarter  of  a  meter  it  is  a  4.D 
lens,  etc. 


LESSON  VI. 

REFRACTION  AND  PHYSIOUK^Y  OF  THE  EVE. 

In  order  that  an  eye  may  receive  a  distinct  visual 
impression  of  an  object,  rays  of  light  from  that  object 
must  be  brought  to  a  focus  on  its  retina.  The  cornea 
and  crystalline  lens  act  as  convex  lenses  in  bringing 
rays  of  light  which  enter  the  eye  to  a  focus  on  the 
retina. 

The  average  width  of  the  pupil  is  4  millimeters,  and 
rays  which  enter  it  from  a  point  6  meters  (20  feet) 
distant  necessarily  diverge  very  slightly,  amounting  at 
the  most  to  only  GTnro-'  therefore  in  estimating  refrac- 
tion rays  from  this  distance  and  greater  are  arbitrarily 
considered  parallel.  When  from  a  point  under  6 
meters  thev  are  considered  divergent. 


Fig.  41. — Parallel  rays  of  light  brought  to  a  focus  on  the  retina  as  in  the 
emmetroijic  eye. 

E.MMETROPIA. 

An  eye,  which  in  a  state  of  rest  brings  parallel  rays 
of  light  to  a  focus  on  its  retina,  has  normal  refraction 
and   is   called   emmetropic    (Fig.    41).     The   principal 
45 


46 


LESSONS    ON    1"HE    EYE. 


focus  of  its  dioptric  system  is  at  its  fo\'ca  centralis, 
and  rays  of  light  from  the  fovea,  after  passing  through 
the  lens  and  cornea  will  be  emitted  parallel  (Fig.  30). 
It  must  be  remembered  that  an  emmetropic  eye  is  not 
necessarily  a  normal  eye  but  is  an  eye  with  normal 
refraction. 

ACCOMMODATION. 

Let  the  vision  of  an  emmetropic  eye  be  concentrated 
upon  a  distant  object,  for  instance,  a  building  across  the 
street,  then  hold  a  pencil  in  the  line  of  vision,  a  foot  in 
front  of  the  eye.  The  building  will  be  distinctly  seen, 
but  the  image  of  the  pencil,  though  visible,  will  be 


CffrneM  pn?per 
Mescemef  Jfemirane 
-E>utolh.eZit.cyru 
Spender Jridis 


'Zmula-ZuuiA  ^^    ' 

VPro, 

Fig.  42. — The  left  half  represents  the  eye  at  rest;  the  right,  during  arconi- 
modatiiMi. 

blurred.  Now  if  the  vision  be  concentrated  upon  the 
pencil  its  outline  will  become  distinct  and  the  image 
of  the  building  will  be  blurred. 

This  instantaneous  difference  in  the  vision  is  effected 
by  the  power  which  the  eye  has  of  changing  its  focus  for 
different  distances. 

We  have  seen  that  an  emmetropic  eye,  in  a  state  of 
rest,  will  focus  upon  its  retina,  all  objects  at  a  distance 
of  twenty  feet  or  over;  that  is,  objects  which  emit 
parallel  rays. 


RKI'RACTION    AND    I'HVSIOI.OCY    OF    THK    KYK.  47 

Rays  from  a  near  object  are  dix'erji^ent,  theretore, 
an  emmetropic  eye  must  increase  its  focal  power  to 
have  distinct  vision  of  a  near  object,  as  it  not  only  has 
to  focus  parallel  rays,  but  has  first  to  make  the  diverg- 
ence parallel.  This  is  accomplished  by  contracting 
the  circular  or  equatorial  fibers  of  the  ciliary  muscle. 
Contraction  of  the  ciliary  muscle  relaxes  the  suspensory 
ligament  and  capsule  of  the  lens.  When  the  pressure 
of  the  capsule  is  relieved  the  lens  becomes  more  convex 
by  an  inherent  elasticity.  Increase  in  its  convexity 
increases  its  focusing  power.  This  power  the  eye 
})ossesses  of  increasing  its  focal  strength  is  called  accom- 
modation (Fig.  42). 

PRESBYOPIA. 

The  elasticity  of  the  crystalline  lens  diminishes 
gradually  from  childhood  to  old  age.  Under  normal 
conditions  this  loss  of  elasticity  is  not  felt  until  about 
the  forty-fifth  year,  but  at  this  period  the  power  of 
accommodating  is  so  lessened  that  convex  glasses  have 
to  be  resorted  to  for  near  vision.  This  physiologic  loss 
of  accommodative  power  is  called  presbyopia.  Weak- 
ness of  the  ciliary  muscle  is  also  a  contributing  factor 
in  presbyopia,  particularly  in  old  age.  As  accommoda- 
tion diminishes  the  reading  glass  must  be  strengthened, 
necessitating  a  change  about  every  two  years. 

CONVERGENCE. 

When  an  eye  is  directed  toward  an  object  so  that  the 
image  of  the  thing  looked  at  falls  upon  the  fovea  cen- 
tralis, the  eye  is  said  to  fix  that  object.     Normally  both 


48 


LESSONS    ON    THP:    EYE. 


eyes  fix  the  same  object,  and  in  order  to  do  this  when 
it  is  brought  near  to  the  face,  both  eyes  have  to  turn 
inward;  the  nearer  the  object  the  more  the  eyes  turn  in. 
The  turning  in  of  the  eyes  necessary  to  fix  near  objects 
is  called  convergence. 

FIELD    OF    VISION. 

When  the  eye  is  fixed  on  an  object,   other  things 
besides  the  one  looked  at  are  visible.     Those  nearest 


Fig.  43. — Field  of  vision  of  a  right  eye.  The  arrow  at  o  being  fi.xed  (looked 
at)  all  objects  on  the  temporal  side  within  the  area  described  by  about  95 
degrees  of  a  circle  are  visible;  all  objects  on  the  nasal  side  within  about  48 
degrees  are  visible.  The  nasal  side  of  the  field  is  restricted  by  the  l)ri(lgc  of 
the  nose. 

the  one  fixed  are  most  di.stinct  and  the  greater  the 
distance  of  an  ol)icct  from  the  one  rtxed,  the  less  dis- 
tinctly is  it  seen.  That  area  in  which  objects  are  \isible. 
the  eye  being  fixed,  is  the  field  of  vision.      It  will  be 


RKFRAt'TIOX    AND    PHVSI01.()(;Y    OF    THK    KVK 


4'; 


seen  from  Fig.  43  that  the  nasal  fidtl  oi  each  eye  ex- 
tends to  about  48  degrees  from  the  object  looked  at, 
therefore  if  both  eyes  look  at  the  same  object  there  is 
an  overlapping  of  the  two  fields,  or  an  area  that  is 
common  to  both  eyes.  This  area  which  extends  to 
about  48  degrees  on  each  side  of  the  object  is  called  the 
binocular  field  of  vision. 

COLOR    PERCEPTION. 

A  ray  of  sunlight  passed  through  a  ]nism  and  pro- 
jected upon  a  screen  forms  a  band  of  colors  ranging 
from  red  to  violet.  The  red  is  toward  the  apex  and 
the  violet  toward  the  base  of  the  prism.      Between  the 


Fig.  44. — B  is  a  screen  which  inlenepts  all  rays  of  light  except  the  ray  A. 
The  prism  C  separates  the  ray  .\  into  the  simple  colors,  red,  orange,  yellow- 
green,  blue  and  violet,  which  are  thrown  on  the  screen  D.  The  violet  rays, 
if  passed  through  the  screen  D,  and  prism  E,  would  show  on  the  screen  F,  as 
violet ;  no  further  rlisintegration  taking  place. 


red  and  violet  there  are  gradations  of  orange,  yellow, 
green,  and  blue.  The  wave  lengths  of  these  colored 
rays  gradually  decrease  from  the  red  rays  which  are 
0.000760  mm.,  to  the  violet,  which  are  0.000397  rnm. 
The  greater  the  wave  length  of  a  ray  of  light,  the  less 
4 


50  LESSONS    ON    THE    EYE. 

it  is  deviated  by  passing  through  a  medium  of  different 
density,  hence  the  power  of  a  prism  to  separate  a  ray 
of  white  hght  into  its  elements.  The  six  colors  of  the 
solar  spectrum,  red,  orange,  yellow,  green,  blue  and 
violet,  are  called  simple  colors  because  it  is  found  by 
passing  any  one  of  them  through  a  prism  that  no  fur- 
ther disintegration  takes  place  (Fig.  44).  Red,  green, 
and  violet  can  be  mixed  to  produce  any  of  the  other 
colors,  but  as  no  combination  can  produce  either  of 
these  three  they  are  called  the  primary  colors. 


Fig.  45. — A  diagram  of  color  perception,  i,  Red;  2,  green;  3,  violet. 
The  height  of  the  curve  from  the  base  line  indicates  the  proportions  in  which 
the  primary  colors  are  mixed  to  produce  the  simple  colors  of  the  spectrum, 
red,  orange,  \-ello\v,  green,  blue  and  violet. 

Many  theories  have  been  offered  to  explain  the 
phenomenon  of  color  perception,  but  none  has  yet  sup- 
planted the  Young- Helmholtz.  This  is  that  we  have 
three  primary  color  perceptions  corresponding  to  the 
three  primary  colors  of  nature,  and  that  there  are  red 
perceptive  fibers,  green  perceptive  fibers  and  violet  per- 
ceptive fibers  in  our  retinas.  These  different  nerve 
fibers  are  stimulated  by  light  waves  of  different  lengths. 
Equal  stimulation  of  all  three  produces  the  sensation  of 
white,  and   just  as  all  the  colors  in  nature  can  1)e  pro- 


RKFRACTION    AND    I'll VSIOI.OGV    OF    THE    EYK.  51 

duced  by  mixing  the  spectrum  red,  green  and  \iolet,  so 
can  every  color  sensation  be  produced  by  stimulation 
of  the  red,  green,  and  violet  perceptive  fibers  in  varying 
proportions.  The  absence  or  imi)airment  of  one  or 
more  of  the  primary  perceptions  constitutes  color-blind- 
ness; the  characteristic  of  the  defect  depending  upon 
which  element  is  missing  or  impaired.  The  theory  of 
Eldridge-Green  assumes  that  there  is  a  color  perceiving 
center  in  the  brain  and  that  defective  color  perception 
is  the  result  of  imperfect  development  of  this  center. 
Congenital  color  blindness  does  not  disturb  vision,  is  not 
dependent  upon  any  demonstrable  pathologic  lesion,  is 
irremediable  and  is  often  hereditary.  There  are  other 
forms  of  color-blindness  depending  upon  diseases  of  the 
retina  and  optic  nerve,  which  will  be  described  in  con- 
nection with  those  diseases. 


LESSON  VII. 

ERRORS  OF  REFRACTION. 

AMETROPIA. 

Any  variation  from  the  state  of  normal  refraction  or 
emmetropia  is  called  ametropia.  Ametropia  appears 
in  three  forms :  hyperopia,  myopia  and  astigmia.  Pres- 
byopia is  not  considered  a  form  of  arrietropia  as  it  is  a 
physiological  change  which  overtakes  the  emmetropic 
as  well  as  the  ametropic  eye. 

HYPEROPIA. 

If  the  focus  of  parallel  rays  is  at  an  imaginary  point 
behind  the  retina,  the  eye  being  at  rest  (z.  e.,  not 
accommodating) ,  it  is  far-sighted  or  hyperopic.  Hyper- 
opia is  due  to  shortness  of  the  antero-posterior  axis  of 
the  eyeball  or  to  lack  of  sufficient  focal  strength  in  the 
cornea  and  lens  (Fig.  46) . 

As  the  fovea  centralis  lies  between  the  dio])tric 
media  of  the  hyperopic  eye  and  their  principal  focus, 
rays  of  light  from  the  fo\-ea,  after  passing  through  the 
lens  and  cornea,  will  be  divergent  (Fig.  32).  If  rays 
from  the  fovea  are  divergent  when  they  lea\-e  an  eye 
only  rays  similarly  conx'crgent  upon  entering  it  will 
be  brought  to  a  focus  on  the  fovea.  There  are  no 
convergent  rays  in  nature,  for  as  we  ha\-e  already 
learned  those  from  20  feet  or  more  are  parallel  and  those 
from  a  point  less  than  20  feet  are  divergent. 
52 


ERRORS    OF    RKl'RACTION.  53 

There  are  but  two  ways  of  con\erging  the  rays  of 
nature  so  as  to  focus  them  u])()n  the  retina  of  the 
hyperopic  eye.  The  eye  must  increase  its  focal 
strength  or  rays  must  l)e  artificially  converged  l^efore 
entering  it. 

By  accommodating,  the  lens  can  increase  its  focal 
strength,  therefore  hypero])ic  eyes  accommodate  con- 


FlG.  46. — The  upper  figure  shows  parallel  rays  of  light  forused  Ijehind  the 
retina  as  in  hyperopia.  The  lower  figure  shows  the  influence  of  a  convex 
lens  in  bringing  the  focus  to  the  retina. 

stantly  for  distant  vision  and  for  near  vision  must  add 
the  amount  of  accommodation  exercised  for  distance 
to  the  amount  it  would  accommodate  if  it  were  em- 
metropic. The  continuous  contraction  of  the  circular 
fibers  of  the  ciliary  muscle  required  by  the  accom- 
modative effort  of  the  hyperopic  eye  causes  a  number 
of  symptoms,  the  most  prominent  of  which  is  headache. 
See  asthenopia,  page  70. 

Rays  may  be  artificially  con\-erged  before  entering  a 


54  LESSONS    ON   THE   EYE. 

hyperopic  eye  by  the  use  of  a  convex  lens,  and  thus 
brought  to  a  focus  on  its  fovea  centrahs  without  any 
accommodative  effort  (Fig.  46) . 

MYOPIA. 

If  the  frcus  of  parallel  rays  is  at  a  point  in  front  of  the 
retina,    the   eye   being   at   rest,    it   is   near-sighted    or 


F"iG.  47. — The  upper  figure  shows  parallel  rays  of  light  focused  in  front  of 
the  retina  as  in  myopia.  The  lower  figure  shows  the  influence  of  a  concave 
lens  in  moving  the  focus  back,  to  the  retina. 

myopic.  Myopia  is  due  to  too  great  length  of  the 
antero-posterior  axis  of  the  eyeball,  or  to  too  great 
focal  strength  of  the  cornea  and  lens  (Fig.  47).  As 
the  fovea  centralis  lies  farther  from  the  dioptric  media 
of  the  myopic  eye  than  their  principal  focus,  rays  of 
light  from  the  fovea,  after  passing  through  the  lens  and 
cornea,  will  be  convergent  and  will  come  to  a  focus  in 
front  of  the  eye  (Fig.  31).     If  rays  from  the  fovea  are 


KRRORS    or    REFRACTION.  55 

convergent  when  they  leave  an  eye  only  rays  similarly 
divergent  u])()n  entering  it  will  he  hrought  to  a  foens 
on  the  fo\-ea.  Only  rays  from  an  ohject  less  than  20 
feet  are  divergent,  hence  distant  objects  are  seen 
poorly  by  a  myopic  eye  and  if  its  error  is  pronounced 
they  are  not  seen  at  all. 

There  is  no  way  of  decreasing  the  focal  strength  of  the 
lens,  therefore  no  effort  on  the  part  of  a  myope  can 
overcome  his  defect.  It  can  be  overcome,  how^ever, 
by  artificially  diverging  rays  before  they  enter  the 
eye.     This  is  accomplished  by  the  use  of  concave  lenses 

(Fig.  47)- 

The  myopic  eye  is  adjusted  for  near  vision  since  only 
divergent  rays  can  be  focused  on  its  retina  and  rays 
from  near  objects  only  are  divergent.  Hence  the  term 
near  sight. 

The  greater  the  degree  of  myopia  the  greater  the 
degree  of  divergence  which  rays  must  have  in  order  to 
focus  on  the  fovea,  and  consequently  the  greater  the 
myopia  the  nearer  an  object  must  be  brought  to  the 
eye  to  see  it  distinctly. 

In  hyperopia  the  effort  of  accommodation  neces- 
sitates the  constant  exercise  of  the  circular  fibers  of  the 
ciliary  muscle,  and  we  find  in  hyperopic  eyes  that  the 
circular  fibers  (Muller's  muscle)  are  increased  in  size 
and  number  as  in  Fig.  48. 

Accommodation  would  make  the  vision  of  a  myopic 
eye  worse,  and  we  find  in  these  eyes  that  the  circular 
fibers  of  the  ciliary  muscle  are  small  in  size  and  number. 

In  myopia  of  high  degree,  when  the  vision  of  the 
patient  is  not  sufficient  for  his  needs  and  no  condition 
exists  contraindicating  the  operation,  removal  of  the 


5^ 


LESSONS    ON    THE    EYE. 


crystalline  lens  may  be  resorted  to.     This  jjroeedure 
has  often  given  most  gratifying  results. 

It  will  be  seen  from  what  has  preceded  that  (without 
lenses)  the  emmetropic  eye  sees  distant  objects  in  a 
state  of  rest  (without  accommodating)   and  must  ac- 


Sriickes  mujcla 


Orbici/Iits  ciliaris. 


P'lG.  48. — Ciliary  body  of  a  hyperopic  eye.      (After  Iwanofl'.) 

commodate  for  near  objects;  the  hyperopic  eye  must 
accommodate  to  see  both  distant  and  near  objects; 
and  the  myopic  eye  sees  distant  objects  imperfectly 
or  not  at  all  and  near  ones  without  accommodating 
unless  the  myo])ia  is  of  low  degree. 

ASTIG.MIA. 

In  emmetropia,  hyperopia  and  myoina,   the  curva- 
ture of  the  cornea  is  the  same  in  e\erv  meridian,  and  its 


KRRORS    ()|-    RK FRACTION.  57 

refractinj^-  ])()wcm-  is  the  sanu'  ihrcms^^li  o\-ery  }xirt,  \-er- 
tical,  horizontal  and  ol)Hque.  All  rays  that  enter  these 
eyes  are  brought  to  a  common  focus.  Sometimes  the 
cornea  has  meridians  of  dififerent  curvature  j^roducing 
greater  refraction  in  some  meridians  than  in  others. 
Such  a  condition  constitutes  astigmia.  In  astigmia 
the  rays  passing  through  the  meridian  of  greatest 
refraction  reach  their  focus  nearest  the  cornea,  while 


■■■I 


Fig.  49.— Appearance  of  lines  running  in  diffeient  directions.     \,  as  seen  hy 
the  normal  eye;  R,  as  seen  by  the  astigmic  eye.     (Jackson.) 

those  passing  through  the  least  refracting  meridian 
come  to  a  focus  farthest  back.  The  meridians  of  high- 
est and  lowest  refracting  power  are  at  right  angles  to 
each  other  and  are  called  the  principal  meridians.  As- 
tigmia is  sometimes  due  to  unequal  curvature  of  the 
meridians  of  the  crystalline  lens  or  to  an  oblique  posi- 
tion of  the  lens  with  regard  to  rays  entering  the  pupil. 
Astigmia  may  be  simple,  compound  or  mixed.  When 
one  of  the  principal  meridians  is  emmetropic  and  the 
other  hyperopic  or  myopic,  the  astigmia  is  simple. 
When  both  principal  meridians  are  hyperopic  but  one 
more  so  than  the  other,  or  both  principal  meridians 
are  myopic,  one  more  so  than  the  other,  the  astigmia 
is  compound.  When  one  principal  meridian  is  hyper- 
opic and  the  other  myopic,  the  astigmia  is  mixed. 


58  LESSONS    ON    THE    EYE. 

The  inequality  of  the  refractive  jxjwer  of  the  principal 
meridians  in  an  astigmic  eye  can  only  be  equalized  by 
the  use  of  a  lens  which  has  different  refractive  power 
in  its  principal  meridians.  This  requisite  is  found  in  the 
cylindric  lens.  A  cylindric  lens  alone  will  correct 
simple  astigmia;  for  compound  and  mixed  astigmia  a 
combination  of  cylindric  and  spheric  lenses  is  necessary. 

ISOMETROPIA,   ANISOMETROPIA    AND    ANTIMETROPI A. 

When  the  refractive  condition  of  a  pair  of  eyes  is  the 
same,  or  if  there  is  any  difference  in  them,  it  is  too 
small  to  be  detected  by  our  present  methods,  they  are 
said  to  be  isometropic. 

If  the  refractive  condition  of  the  two  eyes  is  the  same 
in  kind  but  different  in  degree  they  are  said  to  be  ani- 
sometropic.  A  slight  difference  in  them  is  very  com- 
mon and  can  hardly  be  considered  a  pathologic  state. 
The  term  anisometropic  is  generally  used  when  the 
difference  is  sufficient  to  impair  vision  or  cause  dis- 
turbance of  the  nervous  system. 

If  the  refractive  condition  of  the  two  eyes  is  different 
in  kind  they  are  said  to  be  antimetropic.  The  term 
antimetropia  does  not  refer  to  the  degree  of  error,  which 
may  be  equal  or  unequal. 


LESSON  VIII. 

DISORDERS  OF  THE  OCULAR  MOVEMENTS. 

STRABISMUS. 

Normally  both  eyes  fix  the  same  object.  The  image 
of  the  object  looked  at  falls  upon  the  fovea  centralis  of 
both  eyes.  This  is  accomplished  by  the  co-ordination 
and  association  of  movement  of  the  six  external  ocular 


Fovea  Tovea 

Fig.  50. — The  two  eyes  in  a  state  of  muscular  equilibrium.     The  image  of 
the  candle  A  falls  upon  the  fovea  centralis  of  each  eye. 

muscles  of  each  eye.  In  looking  up,  down,  right  or  left, 
the  eyes  move  together  and  binocular  or  single  vision 
results,  because  the  images  of  objects  in  the  field  of 
vision  fall  upon  identical  parts  of  each  retina,  the  upper 
half  of  the  right  retina  corresponding  to  the  upper  half 
59 


6o  LESSONS    ON    THE    EYE. 

of  the  left,  the  right  or  temporal  side  of  the  right  retina 
to  the  right  or  nasal  side  of  the  left,  etc.  In  this  normal 
state  the  eyes  are  said  to  be  balanced  or  in  equilibrium 
(Fig.  50). 

If  this  association  of  movement  is  disturbed,  so  that 
the  image  of  an  object  falls  upon  the  fovea  centralis  of 
one  eye  and  not  upon  the  fovea  of  the  other,  we  have 
strabismus,  or  squint.  The  eye  which  receives  the 
image  of  the  object  looked  at  upon  its  fovea  is  called 
the  fixing  eye;  the  other  is  called  the  squinting,  or 
deviating  eye.  The  deviation  may  be  in  any  direction, 
depending  upon  which  muscle  or  set  of  muscles  is 
affected. 

Strabismus  is  either  jmralytic  or  comitant. 

PARALYTIC    STRABISMUS 

Is  produced  by  loss  of  power  in  one  or  more  of  the  oc- 
ular muscles.  This  loss  of  power  may  be  total  (paraly- 
sis) or  partial  (paresis) ,  the  latter  being  by  far  the  more 
frequent.  When  the  paralysis  is  confined  to  those 
fibers  of  the  third  nerve  which  supply  the  iris  and  ciliary 
body  the  condition  is  known  as  internal  ophthalmoplegia. 
When  all  the  muscles  of  an  eye  are  paralyzed  except 
those  of  the  iris  and  ciliary  body  the  condition  is  known 
as  external  ophthalmoplegia.  If  both  the  internal  and 
external  ocular  muscles  are  ])aralyzcd  the  condition  is 
known  as  total  ophthalmoplegia. 

Symptoms. —  i.  Movement  of  the  eye  in  the  direction 
of  the  action  of  the  affected  muscle  is  limited  or  lost. 
If  an  external  rectus  is  ])aretic  its  antagonist,  the  inter- 
nal rectus,  will  pull  the  eye  inward.     The  deviation  of 


DISORDERS    OF    THE    MOVEMEiNTS. 


61 


the  afilicted  eye,  the  sound  eye  fixing,  is  called  the 
primary  deviation.  If  the  sound  eye  be  covered  by  a 
card  and  the  paretic  eye  fixes  the  object,  it  will  be  seen 
by  looking  behind  the  card  that  the  sound  eye  has  now 
deviated  in  a  direction  opposite  to  the  i)rimary  devia- 
tion, and  that  the  deviation  is  greater.  This  is  called 
the  secondary  deviation.     In  paralytic  strabismus  the 


fOVEA 

Fig.  51. — The  eye  is  fixed  on  the  candle.  ()l)jccts  in  the  right  field  ;il  C 
are  perceived  by  the  left  side  of  the  retina  at  I).  Objects  at  .A  are  perceived 
bv  the  right  retina  at  B. 


secondary  deviation  is  always  greater  than  the  primary, 
because  the  same  amount  of  nervous  impulse  necessary 
to  produce  a  given  result  in  the  weakened  muscle  is 
also  conveyed  to  its  sound  associate  and  results  in  its 
overaction. 

2.  Diplopia  or  double  \ision  results  because  the 
muscular  imbalance  or  lack  of  equilibrium  prevents 
images  of  objects  in  the  field  of  vision  from  falling  upon 
the  identical  parts  of  each  retina.     The  image  of  the 


62  LESSONS    ON    THE    EYE. 

fixing  eye  is  called  the  true  image;  the  image  of  the 
deviating  eye  the  false  image.  If  an  external  rectus 
is  paralyzed  the  anterior  pole  turns  in,  the  posterior 
pole  out.  The  image  of  the  object  fixed  by  the  sound 
eye  falls  upon  the  retina  of  the  diseased  eye,  to  the 
inner  side  of  the  fovea  centralis  and  is  projected  to  the 
temporal  side  of  its  field.     This  is  due  to  the  fact  that 


Fig.  52. — Convergent  strabismus  of  the  right  eye.  The  image  of  the 
candle  A  falls  on  the  retina  at  the  inner  side  of  the  fovea  and  is  seen  at  B. 
Homonymous  diplopia.     A,  true  image.     B,  false  image. 

the  patient  is  in  the  habit  of  locating  objects  in  the 
temporal  field  which  are  perceived  by  the  nasal  side 
of  the  retina  (Fig.  51)  and  he  does  not  take  into  con- 
sideration the  deviation  of  his  eye.  If  it  is  an  internal 
rectus  that  is  weakened  the  eye  turns  outward  and  the 
image  of  the  object  fixed  by  the  sound  eye  falls  on  the 
retina  of  the  diseased  eye  to  the  outer  side  of  its  fovea 
and  is  projected  to  the  nasal  side  of  the  field. 

Thus  it  will  be  seen  when  the  strabismus  is  con\-ergent 


DISORDERS    Ol-    THE    MOVEMENTS.  63 

the  image  of  the  right  eye  is  on  the  right  side,  the  image 
of  the  left  eye  on  the  left  side.  This  is  called  homony- 
mous diplopia  (Fig.  52). 

When  the  strabismus  is  divergent  the  image  of  the 
right  eye  is  to  the  left,  the  image  of  the  left  eye  to  the 
right.     This  is  called  crossed  or  heteronymous  diplopia 


Righl 


Fig.  53. — Divergent  strabismus  of  the  right  eye.  The  image  of  the 
candle  A  falls  on  the  retina  at  the  outer  side  of  the  fovea  and  is  seen  at  B. 
Heteronymous  diplopia.     A,  true  image.     B,  false  image. 

(Fig.  53).  In  vertical  strabismus  the  lower  image 
belongs  to  the  eye  turned  up,  the  upper  image  to  the 
eye  directed  downward. 

3.  Inaccuracy  in  the  determination  of  the  position  of 
objects  in  that  part  of  the  field  toward  which  the 
affected  muscle  normally  directs  the  eye  is  observed  in 
paralytic  strabismus.  In  looking  toward  an  object  on 
our  right  side,  we  determine  by  experience  its  distance 
to  the  right  by  the  amount  of  innervation  necessary 
to    direct    the    visual    axis    toward    it.     If   the    right 


64  LESSONS    ON    THE    EYE. 

external  rectus  muscle  is  paretic,  an  unusual  amount 
of  energy  is  necessary  to  fix  the  object  and  it  will  seem 
farther  toward  the  right  side  than  it  really  is. 

4.  Vertigo,  nausea  and  headache  are  troublesome 
features  of  paralytic  strabismus.  The  \-ertigo  is 
produced  by  diplopia  and  Ijy  the  inability  to  properly 
locate  objects  in  ])art  of  the  field  of  \-ision. 

5.  A  peculiar  carriage  of  the  head  will  be  observed. 
It  will  be  turned  in  such  a  way  as  to  overcome  the 
diplopia  by  excluding  the  paretic  muscle.  If  the  right 
external  rectus  muscle  is  weakened  the  face  will  be 
turned  toward  the  right  side,  which  is  ec[uivalent  to 
directing  the  gaze  to  the  left,  in  which  act  the  paretic 
muscle  would  have  to  take  no  part. 

Cause. — The  cause  may  be  found  in  the  Ijrain,  the 
nerve-trunk,  or  in  the  muscle  itself.  If  the  lesion  is  in 
the  brain  it  is  said  to  be  central;  if  in  the  ner\-e  or  its 
destribution  it  is  peripheral.  When  the  lesion  is 
central  there  will  probably  be  more  than  one  muscle 
involved,  other  cerebral  symptoms  will  be  present  and 
loss  of  power  in  the  muscle  or  muscles  will  be  gradual 
and  progressive.  When  the  lesion  is  peripheral  the 
paralysis  is  generally  limited  to  one  muscle,  there  are 
no  other  symptoms  and  the  loss  of  power  is  more 
complete.  It  is  due  to  syphilis  in  about  half  of  all 
cases  and  in  the  other  half  to  exposure  to  cold,  rheum- 
atism, diphtheria,  tabes  dorsalis,  diabetes,  poisons, 
tumors,  meningitis,  aneurism,  periostitis,  hemorrhage, 
wounds,  fractures  and  hysteria. 

Treatment. — The  subjective  symj)toms  can  be  relieved 
at  once  by  covering  the  diseased  eye.  If  the  patient 
wears  glasses,  a  ground  glass  (mi  that  side  is  effective. 


DISORDERS    OF    THE    MOVEMENTS.  65 

Treatment  of  paralytic  strabismus  must  depend  upon 
the  cause.  When  due  to  syphiHs  or  rheumatism,  the 
remedies  appropriate  to  these  conditions  are  indicated. 
When  the  result  of  debilitating  causes,  such  as  diph- 
theria, chronic  poisoning,  etc.,  give  general  tonics 
including  strychnin.  A  weak  current  of  electricity 
may  be  tried,  the  positive  pole  being  placed  over  the 
affected  muscle,  the  negative  pole  on  the  back  of  the 
neck.  When  the  deviation  is  slight  and  has  become 
fixed,  relief  is  often  afforded  by  wearing  prisms.  In 
selected  cases  operative  treatment,  tenotomy  or 
advancement,  may  be  helpful. 


LESSON  IX. 

DISORDERS  OF  THE  OCULAR  MOVEMENTS 

{Continued) . 

COMITANT    STRABISMUS. 

Symptoms. — There  is  an  absence  of  the  normal 
association  of  movement  of  the  ocular  muscles  without 
loss  of  their  power.     The  muscles  have  their  normal 


Red,  in  L 


Fig.  54. — Scheme  of  the  action  of  the  ocular  muscles.  Q  E,  direction  of 
traction  of  ext.  recti;  Qj,  I,  of  int.  recti;  S  i,  of  sup.  and  inf.  recti;  a,  b,  of 
inf.  oblique;  c  d,  of  sup.  oblicjue;  (),  point  of  rotation;  (^  Qi,  Transverse 


strength,  but  they  do  not  work  together  so  that  each 
eye  will  fix  the  same  object  at  the  same  lime.  The 
relative  direction  of  the  visual  axis  is  tlisturbed  and 
though  manifested  by  the  de\'iation  of  one  eye,  the 
66 


DISORDERS    OF    'JHE    OCULAR    MOVKMENTS.  67 

motor  apparatus  of  both  eyes  is  inxohed.  The 
primary  and  secondary  deviations  are  equal  The 
deviation  may  be  monolateral  or  alternating;  if  the 
latter,  vision  in  each  eye  will  probably  be  the  same. 
Internal  comitant  strabismus  (esotropia)  is  a  condition 
which  usually  manifests  itself  early  in  life,  the  average 
age  being  about  three  years.  Divergent  comitant 
strabismus  (exotropia)  usually  manifests  itself  at 
about  the  age  of  puberty  or  a  little  later.  The  strabis- 
mus may  be  vertical ;  the  right  or  left  eye  may  deviate 
upward  (right  or  left  hypertropia) .  Diplopia  is  rare 
in  comitant  strabismus;  the  squinting  eye  is  often  so 
amblyopic  as  not  to  perceive  the  false  image,  and  if  it 
has  good  vision,  comitant  squint  arises  so  early  in  life 
that  there  is  developed,  with  the  growth  of  the  child,  a 
power  of  the  mind  to  exclude  the  false  image. 

Cause. — There  is  more  to  discover  relative  to  the 
cause  of  comitant  strabismus  than  has  yet  been 
revealed,  but  the  following  may  be  given  as  etiological 
factors : 

I.  Hyperopia  exists  in  three-fourths  of  all  cases  of 
internal  comitant  strabismus.  Convergence  and  ac- 
commodation are  associated  actions,  and  in  hyperopia 
there  is  excessive  accommodation  and  the  associated 
convergence  sometimes  amounts  to  internal  strabismus. 
Relief  of  the  hyperopia  by  convex  glasses  will  at  times 
straighten  these  eyes.  But  that  hyperopia  is  not  a 
prime  factor  in  the  production  of  strabismus  is  proven 
by  the  fact  that,  in  the  majority  of  cases,  the  correction 
of  the  hyperopia  by  glasses  has  no  effect  on  the  strabis- 
mus, and  also  that  there  are  so  many  cases  of  high 
degree  of  hyperopia  in  which  there  is  no  strabismus. 


68  J,ESSONS    ON    THE    EYE. 

2.  Myopia  is  associated  with  divergent  strabismus 
and  the  explanation  is  that  the  convergence  necessary 
to  focus  at  the  far  point  of  a  myopic  eye,  which  is  very 
close  to  the  face,  puts  too  great  a  strain  on  the  internal 
rectus  muscles,  one  of  them  gives  up  and  divergence 
results.  The  exception  to  this  rule  is  proven  by  the 
fact  that  only  a  very  small  proportion  of  the  cases  of 
myopia  diverge. 

3.  Amblyopia  or  poor  vision  in  the  squinting  eye  is 
found  in  many  cases  of  strabismus  (72  per  cent.,  Nagel) 


Fig.  55. — Large  and  small  strabismus  hooks. 

and  the  weight  of  authority  is  in  fa\'or  of  the  view  that 
the  amblyopia  is  congenital  and  is  the  cause  of  the 
strabismus,  the  stimulation  to  binocular  vision  not 
being  present.  However,  a  respectable  minority  claim 
the  amblyopia  to  be  the  effect  of  non-use  of  the  squint- 
ing eye  and  not  the  cause  of  the  strabismus.  But  that 
congenital  amblyopia  is  only  a  factor  in  the  production 
of  squint  is  proven  by  the  absence  of  squint  in  the 
majority  of  amblyopic  eyes. 

4.  Unusual  development  of  a  single  ocular  muscle 
is  another  possible  element  in  the  production  of 
comitant  strabismus,  the  internal  rectus  being  often 
unnaturally  strong  in  internal  strabismus  and  the  same 
is  true  of  the  external  rectus  when  the  deviation  is 
outward , 


DISORDERS    OF    TI1['.    OCULAR    MOVF.MKNTS.  69 

5.  Defective  development  of  the  fusion  faculty  is  suj)- 
posed  to  be  a  cause  of  strabismus.  The  faculty  of 
fusing  the  images  of  the  two  eyes  into  one  is  a  cerebral 
process  developed  early  in  life. 

Treatment.  —  Rarely  comitant  strabismus  disaj)- 
pears  without  medical  aid.  Sometimes  it  is  entireh- 
removed  by  wearing  the  glass  which  corrects  the  total 
refractive  error,  consequently  these  eyes  should  be 
tested  and  the  proper  glasses  ordered  as  soon  as  the 
child  is  old  enough  to  wear  them.  It  is  also  good 
practice  to  cover  the  fixing  eye  with  a  bandage  for  a 
part  of  each  day  to  compel  the  use  of  the  deviating  eye. 
Numerous  exercises  for  the  de\-elopment  of  the  fusion 
faculty  have  been  devised.  Every  method  of  this  kind 
should  be  faithfully  used  before  resorting  to  surgical 
interference. 

The  treatment  for  the  remaining  cases  is  operative, 
tenotomy  of  the  over-acti\'e  muscle  or  advancement  of 
its  antagonist.  Operations  for  strabismus  should  not 
be  performed  before  seven  or  eight  years  of  age,  except 
in  rare  cases,  owing  to  the  tendency  to  development  of 
over-effect  with  the  growth  of  the  child. 

INSUFFICIEXCY  OF  THE  OCULAR  MUSCLES,  HETEROPHORIA 
OR    LATENT    SQUINT. 

This  condition  differs  from  strabismus  only  in  degree, 
the  tendency  to  deviation  being  overcome  by  the  desire 
for  binocular  vision.  It  may  be  comitant  or  paretic. 
There  is  lack  of  balance  of  the  ocular  muscles  l:)ut 
parallelism  of  the  visual  lines  is  maintained  by  an 
unconscious  effort  on   the  part  of  the  patient.     The 


70  LESSONS    ON    THE    EYE. 

effort  to  maintain  this  parallelism  and  secure  binocular 
vision  generally  results  in  asthenopia,  which  may  be 
manifested  by  pain  over  the  insertion  of  the  weak 
muscle,  blurred  vision,  inability  to  do  close  or  pro- 
tracted work,  photophobia,  subacute  congestion  of  the 
conjunctiva,  headache,  vertigo  and  other  neuroses.  The 
following  terms  were  introduced  by  Stevens  to  indicate 
the  conditions  present  in  latent  squint:  Orthophoria, 
perfect  balance  of  the  ocular  muscles.  Heterophoria, 
imperfect  balance  of  the  muscles  or  latent  squint. 
Esophoria,  a  tendency  inward  or  latent  convergence. 


Fig.  56. — Strabometer.     A  simple  but  inaccurate  instrunienl  for  measuring 
the  amount  of  deviation  in  strabismus. 

Exophoria,  a  tendency  outward  or  latent  divergence. 
Hyperphoria,  a  tendency  of  the  visual  axis  of  one  eye 
higher  than  the  other. 

Jackson  applies  the  term  insufficiency  of  the  ocular 
muscles  to  latent  paralytic  squint  and  limits  Stevens' 
nomenclature  to  latent  comitant  squint. 

Cause. — The  same  as  in  manifest  paralytic  strabismus 
and  manifest  comitant  strabismus. 

Diagnosis. — The  cover  test  will  reveal  a  latent  squint 
of   2   or  3   degrees  or  more.     Tt   is  made  as  follows: 


DISORDF.RS    OF    THK    OCULAR    MOVEMENTS.  J I 

Ha\-c  the  patient  fix  one  eye  on  an  o!)ject  at  a  distanee 
of  20  feet.  Cover  the  other  with  a  card.  Binocular 
vision  as  well  as  diplopia  are  now  impossible  and 
therefore  the  influence  which  stimulates  the  patient  to 
overcome  this  tendency  toward  deviation  is  no  longer 
active.  The  muscle  or  muscles  w'hich  have  recei\'ed 
the  excess  of  innervation  will  relax  and  the  covered  eye 
will  slowly  assume  the  position  in  which  the  muscles  are 
at  rest.  When  the  card  is  removed  the  covered  eye  will 
quickly  return  to  the  position  of  binocular  fixation. 
The  direction  of  this  quick  mo\-ement  of  the  eye  is 
opposite  to  the  deviation  and  the  amount  of  the  devia- 
tion and  recovery  are  equal. 

There  are  numerous  instruments,  found  in  every  eye 
clinic,  for  the  determination  of  the  nature  and  amount 
of  latent  squint.  It  is  not  necessary,  therefore,  to 
describe  them  in  this  abbreviated  text. 

Treatment. — The  treatment  of  this  condition  is 
difficult  and  belongs  to  the  oculist.  Careful  correction 
of  any  refractive  error  is  of  first  importance.  The 
constitution  should  be  appropriately  treated  and  use 
of  the  eyes  regulated.  In  some  cases  wearing  prisms 
gives  relief.  There  are  methods  of  exercising  the 
weak  muscle  which  may  restore  the  necessary  power. 
As  a  last  resort  operative  measures  may  be  adopted, 
which  consist  in  tenotomy  of  the  over-active  muscle 
or  advancement  of  the  weak  one. 

NYSTAGMUS. 

This  condition  is  characterized  by  rapid,  involuntary 
oscillation  of  the  eyeballs,  generally  in  the  lateral 
direction.     It    may    be    congenital    or    ae(|uire(l    and 


72  LESSONS    ON    THE    EYE. 

nearly  always  affects  both  eyes.  If  acquired,  the 
patient  will,  at  first,  complain  of  the  movement  of 
objects  looked  at. 

Cause. — Defective  development  of  the  eyes,  albinism, 
bad  vision  from  corneal  and  lenticular  opacities, 
blindness  and  protracted  use  of  the  eyes  in  an  abnormal 
position,  it  being  common  with  miners  who  work  with 
their  eyes  directed  obliquely  upward.  It  is  also  due  to 
l)rain  lesions  of  central  origin,  ataxia  and  tumors  of  the 
cerebellum. 

Treatment. — Improve  vision  by  all  possible  means; 
if  there  is  any  refractive  error  put  on  the  correcting 
glass;  if  there  is  a  central  corneal  scar  make  a  false  pupil. 
In  case  of  strabismus  do  a  tenotomy  or  advancement, 
and  if  the  occupation  is  at  fault  change  it  at  once.  The 
great  majority  of  cases  of  nystagmus  get  little  or  no 
relief. 


LESSON  X. 

DISEASES  OF  THE  LIDS. 
bl?:pharitis. 

This  is  an  inflammation  of  the  lid  border  character- 
ized by  the  following  symptoms  given  in  the  order  of 
their  severity,  i.  Hyperemia,  itching  and  slight  swell- 
ing. 2.  Seborrhea  or  hypersecretion  of  the  sebaceous 
glands.  The  dried  sebum  forms  yellaw  crusts  on  the 
border  of  the  lid.  3.  Ulceration  at  the  root  of  the 
lashes.  4.  Thickening  of  the  edge  of  the  lid.  5. 
Falling  of  eyelashes  with  atrophy  of  their  follicles. 
6.  Ectropion  with  eversion  of  the  lacrymal  puncta  and 
resulting  epiphora. 


-Blepharitis,  eyelashes  matted  into  bundles  h}-  the  secretion  alonf]; 
lid  borders. 

Cause. — It  is  sometimes  eczematous  in  nature  and  is 
most  frequently  found  in  the  fair-skinned,  the  strumous 
and  the  badly  nourished.  Chronic  conjunctivitis, 
lacrymal  obstruction,  errors  of  refraction,  exposure  and 
abuse  of  eyes  are  causative.  It  frecjuently  follows  the 
exanthematous  fevers.  The  disease  is  limited  to  no 
age  but  is  most  frequent  in  children. 
73 


74  LESSONS    ON    THE    EYE. 

Treatment. — Correct  the  refractive  error.  Protect 
eyes  from  the  irritation  of  dust,  smoke,  etc.  Treat 
the  constitution  with  cod  hver  oil,  iron  and  arsenic  if 
struma  or  debihty  are  present.  If  there  are  ulcers 
around  the  cilia  pull  out  the  lashes  so  affected  and 
touch  the  ulcers  with  nitrate  of  silver  stick.  Rub  into 
the  edge  of  lids,  once  a  day,  an  ointment  of  the  yellow 
oxid  of  mercury,  gr.  h  to  vaseline  5i,  or  an  ointment 
of  ammoniatcd  mercury,  gr.  h  to  oi-  Before  applying 
the  ointment  all  secretion  should  be  cleansed  from 
the  lid  border.  Eight  grains  of  biborate  of  soda  to 
one  ounce  of  warm  water  will  be  found  useful  in 
removing  the  crusts.  If  there  is  lacrymal  obstruction 
it  must  receive  appropriate  attention.  In  the  chronic 
stage  of  blepharitis  stimulating  tar  ointments  are 
recommended  but  in  the  majority  of  cases  mild  and 
soothing  measures  will  be  the  most  efficacious. 

HORDEOLUM. 

A  stye  is  an  acute  inflammation  of  a  sebaceous  gland 
at  the  lid  border.  It  is  usually,  in  appearance  and 
symptoms,  a  small  boil,  but  sometimes  produces 
general  edema  of  the  lid  with  chemosis  of  the  con- 
junctiva. 

Cause. — Error  of  refraction,  general  del)ility,  con- 
stipation, and  germ  infection. 

Treatment. — Use  hot  applications  to  bring  the 
inflammation  to  a  focus,  then  ojx'n.  Correct  the 
constitutional  condition  if  debility  exists.  Correct 
refractive  errors  and  remo\'e  any  source  of  local 
irritation.     vSulfid  of  calcium,    \  grain  twice  a  day  or 


DISEASES    OF    THE    LIDS.  75 

dilute  sulfuric  acid  ten  drops  after  each  meal  may  be 
given.  A  stye  can  sometimes  he  alnjrted  in  the 
earliest  stages  by  the  use  of  cold  a])])lications. 

CHALAZION. 

This  .small  tumor  of  the  lid  is  due  to  a  chronic  inflam- 
mation   of    a    Meibomian    gland.      Hala    claims    this 


Fig.  58. — Chalazion  of  upper  lid. 

iniiammation  to  be  the  product  of  the  xerosis  bacillus. 
Its  development  is  gradual  and  usually  without  any 
symptoms  which  annoy  the  patient.  The  inflam- 
matory process  causes  proliferation  of  the  epithelial 
lining  of  the  gland  and  cell  infiltration  of  the  surround- 
ing tissue.  This  inflamed  area  develops  into  a  granu- 
lation mass  surrounded  by  a  thin  connective  tissue 
capsule.  The  granuloma  tends  to  break  down  in  the 
center,  forming  a  liquid,  which  may  become  jnu-ulent. 
Rarely  the  mass  becomes  fibrous  and  solid. 


76 


LESSONS    ON    THE    EYE. 


Treatment. — The  contents  may  escape  and  the 
tumor  disapj^ar  spontaneously.  Sometimes  they  can 
be  cured  by  hot  apphcations,  massage  and  ammoni- 
ated  mercury  ointment.  An  operation  is  generally 
necessary.  The  incision  may  be  made  through  the  skin 
or  conjunctiva,  depending  upon  the  proximity  of  the 


Fig.  5q. — A,  method  of  applying  lid  forceps  for  removal  of  i  halazion  throuj: 
the  conjunctiva;  B,  lid  forceps. 


tumor  to  these  surfaces.  If  the  incision  is  in  the  skin 
it  should  be  made  parallel  with  the  lid  border  so  as  not 
to  divide  unnecessarily  the  fibers  of  the  orbicularis 
muscle.  If  the  incision  is  made  through  the  con- 
junctiva it  should  be  vertical  to  the  lid  border  to  avoid 
cutting  the  ducts  of  the  Meibomian  glands.  If  the 
tumor  is  soft  enough  a  curette  will  remove  it.  Some- 
times, to  accomplish  a  thorough  removal,  it  has  to  be 
dissected  out. 


DISEASES    OF    THE    LIDS.  77 

TRICHIASIS. 

W'iKl  hairs,  misplaced  or  misdirected  eyelashes 
rubbing,  the  globe,  produce  great  pain  and  blepharo- 
spasm and  may  cause  ulceration  and  subsequent 
opacity  of  the  cornea. 

Cause. — If  the  trichiasis  is  partial  it  may  be  con- 
genital or  may  be  due  to  the  cicatricial  contraction 
following  styes,  blepharitis  ulcerosa,  traumatism,  etc. 
If  there  is  a  complete  trichiasis  it  is  usually  associated 
with  entro])ion  and  is,  as  a  rule,  the  result  of  trachoma. 


Fig.  ()o. — Trichiasis  of  upjier  lid. 

Treatment. — i.  Epilation  or  pulling  out  of  the 
offending  hairs  is  only  of  temporary  benefit,  as  they 
grow  in  again.  2.  Electrolysis,  introduced  by  Michel 
of  St.  Louis,  is  valuable.  A  needle  attached  to  the 
negative  pole  is  passed  to  the  hair  bulb,  which  is  killed 
by  a  current  of  about  five  milliamperes.  This  procedure 
is  exceedingly  painful.  3.  Excision  of  the  misplaced 
hairs  with  their  bulbs  is  useful  when  they  are  few 
in  number  and  close  together.  4.  If  the  wild  hairs 
are  isolated  their  direction  can  be  changed  by  passing 
a  needle,  threaded  with  a  loop,  through  the  lid  in  the 


78  LESSONS    ON    THE    EYE. 

direction  you  wish  the  hair  to  take,  then  catching  the 
hair  in  the  looj)  and  drawing  it  through  the  tissues  as 
you  puh  the  thread  through.  5.  When  the  trichiasis  is 
total  and  the  hd  border  is  turned  inward,  one  of  the 
operations  for  entropion  should  be  done. 

ENTROPION    AND    ECTROPION. 

Entropion  is  a  turning  in  of  the  lid.  Ectropion  is  a 
turning  out  of  the  lid. 

I.  We  have  spasmodic  entropion  and  spasmodic 
ectropion. 

Spasmodic  contraction  of  the  fibers  of  the  orbicularis 
near  the  lid  border  in  conjunction  with  a  relaxed  and 


Fig.  61. — Entropion  of  the  lower  lid.      (.\fter  Mackenzie.) 

flabby  skin  and  a  deep-set  eyeball  causes  the  lid  border 
to  turn  inward,  producing  spasmodic  entropion,  which 
is  nearly  always  found  in  the  aged.  This  condition 
occurs  almost  without  exception  in  the  lower  lid. 
Spasmodic  contraction  of  the  fibers  of  the  orbicularis 
farthest  from  the  lid  border,  in  conjunction  with  a  tense 
skin,  congested  and  thickened  conjunctiva  or  a  promi- 
nent  eyeball,    cau.ses  the  lid  border  to  turn  outward 


DISKASKS    OF    THE    LIDS.  79 

producing  spasmodic  ectropion,  which  is  nccui)'  ah\'ays 
found  in  children  and  young  people. 

2.  We  have  cicatricial  entropion  and  cicatricial 
ectropion. 

Trachoma',  some  forms  of  conjunctivitis  and  wounds 
may  produce  cicatricial  contraction  of  the  conjunctiva 
lining  the  lid  which  turns  the  edge  of  the  lid  inward, 
causing  entropion. 


Fig    62  — Ectropion  ot  lower  lid 


Burns,  wounds,  ulcers,  caries  of  the  orbital  border  and 
other  causes  may  produce  cicatricial  contraction  of  the 
skin  of  the  lid,  which  turns  the  edge  of  the  lid  outward, 
causing  ectropion. 

We  have,  in  addition  to  the  above  conditions,  a 
paralytic  ectroj^ion  due  to  paralysis  of  the  orbicularis 
muscle.  The  lower  lid  falls  outward  and  away  from  the 
globe  by  its  own  weight.  The  lower  lid  is  the  only  one 
affected  by  paralytic  ectropion. 

The  treatment  is  almost  always  o])erative.  Spas- 
modic entropion  can  be  temporarily  relie\-ed  by  paint- 
ing the  skin  over  the  inferior  orbital  margin  with 
collodium,  contraction  of  which  everts  the  lid  border. 


8o  LESSONS    ON    THE    EYE. 


ANKYLOBLEPHARON. 


The  edges  of  the  upper  and  lower  hd  may  grow  to- 
gether producing  a  condition  called  ankyloblepharon. 
It  may  be  congenital  or  acquired;  partial  or  complete. 


Fig.  63. — Ankyloblepharon. 

The  cause  is  some  accident  or  disease  which  leaves  the 
lid  margins  in  a  denuded  and  granulating  state.  If 
in  this  condition  the  raw  surfaces  are  kept  in  apposition 
they  will  grow  together. 


LESSON  XI. 

DISEASES  OF  THE  LIDS   (Continited). 

BLEPHAROSPASM. 

Spasm  of  the  orbicularis  appears  under  a  variety  of 
forms:  i.  Abnormal  frequency  of  winking  or  nictita- 
tion may  be  an  unconscious  habit  which  sometimes 
lasts  a  life-time.  2.  A  similar  manifestation  is  seen  in 
children,  due  to  chronic  conjunctivitis,  V)ut  it  may  be 
the  beginning  of  a  general  chorea.  3 .  In  hysteria  there 
is  sometimes  pronounced  blepharospasm,  which  may 
be  tonic  or  clonic.  4.  In  old  age  a  tonic  blepharo- 
spasm, which  resists  all  treatment,  may  occur  (Fuchs). 
5.  A  reflex  spasm  of  the  orbicularis  may  be  due  to 
trichiasis,  corneal  and  conjunctival  diseases,  foreign 
bodies,  errors  of  refraction,  and  to  any  condition  which 
can  cause  photophobia.  Treatment  is  to  remove  the 
cause.  6.  There  is  a  clonic  form  of  blepharospasm 
corresponding  with  tic  douloureux,  which  is  very  pain- 
ful. At  gi\'en  intervals  the  cramp  seizes  the  orbicularis 
and  other  muscles  of  one  side  of  the  face,  causing  dis- 
tortion and  great  pain.  The  paroxysm  passes  off  in 
about  a  minute,  to  be  repeated  again  after  an  interval 
varying  in  length  in  different  cases.  An  average  of 
four  to  six  attacks  an  hour  have  been  observed.  The 
cause  is  some  nerve  or  brain  lesion,  and  treatment  is 
very  ineffectual.  lodid  and  bromid  of  potassium  have 
each  been  beneficial.  If  any  peripheral,  exciting  cause 
can  be  discovered,  it  should  be  removed. 

6  81 


82  LESSONS    ON    THE    EYE. 

LAGOPHTHALMIA. 

Lagophthalmia  is  an  inability  to  close  the  lids.  Con- 
stant exposure  of  the  globe  causes  conjunctivitis, 
ulceration  of  the  cornea,  and  an  overflow  of  tears,  due 
to  the  malposition  of  the  punctum.  The  evils  of 
lagophthalmia  are  lessened  by  the  tendency  of  the 
cornea  to  turn  upward  under  the  lid  when  an  effort  to 
close  the  palpebral  fissure  is  made.  This  also  occurs 
in  sleep. 

Cause. — I.  Protrusion  of  the  eyeball  as  in  exophthal- 
mic goitre  or  orbital  tumors.  2.  Large  anterior  staphy- 
loma. 3.  Congenital  shortening  of  the  lids.  4.  Loss 
of  lid  tissue  from  lupus,  burns,  etc.  5.  Ectropion. 
6.  Paralysis  of  the  seventh  nerve.  The  course  of  this 
nerve  is  long  and  devious,  and  it  passes  through  numer- 
ous tissues,  which  exposes  it  to  accident  or  disease. 

Treatment. — The  treatment  consists  in  removing  the 
cause,  meanwhile  protecting  the  cornea  from  irritation 
by  covering  the  eye  with  a  bandage  or  holding  the  lids 
together  with  adhesive  plaster.  In  the  erect  position, 
the  force  of  gravity  will  help  to  draw  the  lid  down  o\-er 
the  cornea.  In  some  cases  tarsorrhaphy  is  necessary. 
This  consists  in  shortening  the  palpebral  fissure  by 
uniting  the  edges  of  the  lids. 

PTOSIS. 

Ptosis  is  a  complete  or  partial  drooping  of  the  upper 
lid.  Vision  may  be  obstructed  by  the  lids  covering 
the  ]3upils.  To  prevent  this  the  patient  throws  his 
head  backward  and  tries  to  raise  the  lids  by  elevating 
the  brows.  If  congenital  it  is  frequently  bilateral; 
when  acquired  it  is  generally  unilateral. 


DISEASES    OF    THE    LIDS. 


83 


Caitsc- -The  causes  of  congenital  j^tusis  are:  1.  De- 
ficient development  or  absence  of  the  levator  palpe- 
brcB  superioris  muscle.  2.  Injury  inflicted  by  the 
forceps  in  difficult  delivery.  3.  Defective  attachment 
of  the  skin  to  the  underlying  tissues,  ]:>roducing  that 


Fig.  64. — Acquired  ptosis  of  syphilitic  origin.     The  effort  to  raise  the  lids 
by  elevating  the  eyebrows  is  shown. 


form    called   ptosis    adiposa,    in    which    the    skin    falls 
over  the  lid  border  like  a  pouch. 

The  causes  of  acquired  ptosis  are :  1 .  Injury  to  the 
levator  muscle.  2.  Paralysis  of  the  third  nerve,  usually 
from  syphilis  (Fig.  64).  3.  Thickening  of  the  lids  by 
new  growths,  trachoma,  etc.     4.  Hysteria. 


84  LESSOiNS    ON    THE    EYE. 

Treatment. — Attack  the  cause  when  it  can  be  located. 
The  congenital  forms  require  operations.  In  paralysis 
use  anti-syphilitic  and  anti-rheumatic  measures.  Elec- 
tricity, one  pole  back  of  the  ear  and  the  other  over  the 
lid,  mav  be  tried. 


ECZEMA. 

Eczema  of  the  lids  is  most  frequently  met  with  in 
children  who  have  phlyctenular  ophthalmia,  and  in 
adults  with  an  irritating  discharge  from  the  eye.  The 
symptoms  and  treatment  are  the  same  as  of  eczema 
in  other  parts.  In  an  acute  case  treatment  should  be 
mild  and  soothing ;  when  chronic  it  can  be  more  stimu- 
lating. Dust  with  starch  powder  or  aristol.  Apply 
oxid  of  zinc  ointment  to  which  carbolic  acid,  5  grains 
to  the  ounce,  may  be  added*.  Yellow  oxid  of  mercury 
ointment  is  useful,  as  is  also  painting  with  nitrate  of 
silver  solution,  10  to  20  grains  to  the  ounce. 


HERPES    ZOSTER    OPHTHALMICUS. 

This  term  is  applied  to  shingles  following  the  course 
of  the  first  and  second  divisions  of  the  fifth  nerve.  It 
is  characterized  by  redness  and  swelling  of  the  skin  and 
the  formation  of  vesicles  on  the  forehead,  eyelids  and 
nose.  The  disease  is  very  painful  and  is  a  menace  to 
sight  if  the  vesicular  eruption  appears  on  the  cornea. 
A  severe  neuralgia  generally  precedes  the  attack  and 
may  persist  for  a  long  time  after  it.  The  cause  of  the 
disease  is  an  inflammation  of  the  fifth  nerve  of  an  ob- 
scure   character.     Treatment    is    unsatisfactory.     The 


DISEASES    OF    THE    I.TDS.  85 

Vesicles  should  not  be  ruptured  and  when  they  dry  form- 
ing crusts,  the  latter  should  remain  undisturbed.  Pick- 
ing off  the  crusts  deepens  the  subsequent  scars.  Ano- 
dynes may  be  required.  Internally  salicylic  acid  and 
quinin  have  both  l)een  recommended. 


Fig.  65.— Clamp  used  lo  prevent  hemorrliage  and  steady  the  part   in   lid 
operations. 


PHTHIRIASIS. 


Crab  lice  may  get  into  the  eyelashes  and  give  rise  to 
excessive  itching ;  the  consequent  rubbing  and  scratch- 
ing of.  the  lids  sets  up  a  mild  inflammation  which  may 
be  mistaken  for  blepharitis.  The  hce  and  their  eggs 
may  be  seen  on  the  cilia.  Treatment  is  to  rub  the  lid 
border  and  lashes  thoroughly  with  mercurial  ointment 
every  night  until  the  parasites  are  killed. 

ECCHYMOSIS    OF    THE    LIDS. 

A  "black  eye"  is  the  result  of  any  cause  which  rup- 
tures a  blood  vessel  of  the  subcutaneous  tissue  of  the 
lid.  It  is  most  frequently  due  to  a  blow^  Time  is 
the  only  cure.  A  bandage,  cold  applications  immedi- 
ately after  the  accident,  arnica  or  lead  and  opium  wash 
will  assist.  When  all  subcutaneous  oozing  has  ceased 
and  the  clot  is  formed  its  absorption  may  be  hastened 
by  hot  applications  and  gentle  massage. 


86  LESSONS    ON    raE    EYE. 

Epithelioma  or  rodent  ulcer  of  the  lids  is  not  a  rare 
disease  in  elderly  people.  Its  site  of  election  is  at  the 
margin  near  the  inner  canthus  and  usually  on  the  lower 
lid.  It  develops  slowly.  The  absence  of  other  evi- 
dences of  syphilis  will  assist  in  differentiating  it  from  a 
syphilitic  ulcer.  It  can  be  distinguished  from  lupus  by 
the  fact  that  lupus  begins  much  earlier  in  life  and  ex- 
tends to  the  lids  from  its  starting  point  on  some  other 
part  of  the  face.  Excision,  caustics  and  cautery  are 
the  methods  advised  for  its  removal.  The  tendency  to 
recurrence  at  times  renders  all  these  methods  useless. 
The  X-ray  has  been  found  curative  in  these  cases  and 
should  be  tried. 

Sarcoma  of  the  lids  is  rare.  Lupus,  molluscum 
contagiosum,  xanthelasma,  milium  and  nevus  are 
diseases  of  the  skin  of  the  lids  whose  description  be- 
longs more  properly  to  a  work  on  skin  diseases.  Ery- 
sipelas may  attack  the  lids,  and  if  it  extends  to  the 
orbital  tissues  there  is  some  danger  of  serious  conse- 
quences, such  as  orbital  abscess,  optic  neuritis,  optic 
atrophy,  thrombosis  of  the  retinal  vessels,  and  throm- 
bosis of  the  intra-cranial  venous  sinuses. 

The  primary  syphilitic  sore  has  been  known  to  appear 
upon  the  lids.  The  various  eruptions  of  secondary 
syphilis  and  tertiary  ulceration  are  more  common. 
Syphilitic  ulceration  must  not  be  mistaken  for  lupus  or 
epithelioma. 


LESSON  XII. 

DISEASES  OF  THE  LACRYMAL  APPARATUS. 


EPIPHORA. 

The  lacrymal  system  is  divided  into  a  secretory  part, 
the  glands,  and  an  excretory  or  drainage  part,  the 
puncta,  canaUcuH,  sac  and  duct.  Normally  the  lacry- 
inal  secretion  is  about  balanced  by  evaporation.  When 
the  tears  overflow  on  to  the  cheek  the  condition  is 
called  epiphora.     It  is  the  most  constant  and  significant 


Fig.  66. — Fistula  of  lacrymal  sac 

symptom  of  disease  of  the  lacrymal  apparatus.  There 
are  two  forms  of  epiphora;  one  related  to  the  secre- 
tion and  the  other  to  the  drainage  of  tears. 

I.  Epiphora  caused  by  excessive  secretion  may  be 

due  to  the  influence  of  certain  emotions  such  as  grief 

or  laughter;  acute  disease  particularly  of  the  cornea 

and  iris;  chronic  conjunctivitis  and  irritation  of  the 

87 


88  LESSONS  ON  thp:  eye. 

conjunctiva  by  foreign  l)odies,  wind,  dust  or  smoke; 
irritation  of  the  retina  by  bright  hght;  irritation  or 
disease  of  the  mucous  membrane  of  the  nose;  and 
neuralgia  of  the  fifth  ner\-e.  This  form  is  called  reflex 
epiphora. 

2.  Epiphora  caused  by  impairment  of  the  drainage 
apparatus  may  be  due  to  eversion  or  occlusion  of  the 
puncta,  plugging  or  stricture  of  the  canahculi,  inflam- 
mation of  the  sac  or  stricture  of  the  duct.  The  amount 
of  epiphora  resulting  from  defective  drainage  alone  is 
either  not  appreciable  or  very  slight  as  evaporation 
will  about  dispose  of  the  normal  secretion.  It  would 
follow,  then,  that  obstruction  of  the  drainage  apparatus 
must  be  associated  with  some  condition  productive 
of  hypersecretion  of  tears  in  order  to  cause  epiphora. 
A  moderate  hypersecretion  of  tears  will  not  cause 
epiphora  if  the  drainage  apparatus  is  patulous,  as  the 
fluid  will  be  carried  into  the  nose,  but  with  the  drainage 
obstructed  the  smallest  excess  of  tears  must  overflow 
the  hds. 

DISEASES    OF    THE    LACRYMAL    GLAND. 

I.  Inflammation  of  the  lacrymal  gland  occurs  very 
rarely.  It  may  be  acute  or  chronic.  There  would  be 
the  usual  symptoms  of  inflammation  which  might 
result  in  suppuration  or  recover  without  it.  There  is 
often  difficulty  in  excluding  orbital  celluHtis,  phlegmon 
of  the  lid  and  periostitis,  owing  to  the  pronounced 
chemosis  of  the  conjunctiva  and  great  swelling  and 
tenderness  of  the  parts.  Treatment  consists  of  hot 
bichlorid  fomentation,  anodynes  and  evacuation  of  the 
pus  if  formed . 


DISEASES    OF    THE    J.ACRYMAL   APPAR.\TUS.  89 

2.  Dislocation  of  the  latTymal  sj;land  appears  as  a 
movable  tumor  under  the  ocular  conjunctiva  at  the 
upper  and  outer  part  of  the  globe.  Treatment  does 
not  avail.     Extirpation  may  be  resorted  to. 

3.  Tumors  of  numerous  varieties  may  develop  in  the 
lacrymal  gland.  Hypertrophy  and  atrophy  have  been 
observed.  A  tumor  or  hypertrophy  of  the  gland  would 
tend  to  force  the  eyeball  downward  and  inward,  caus- 
ing diplopia.  If  the  growth  developed  behind  the 
ball  exophthalmos  would  follow.  Extirpation  of  the 
diseased  gland  is  the  only  measure  likely  to  prove 
beneficial. 

4.  Fistula  of  the  gland  is  generally  the  result  of  an 
abscess  or  injury.  A  connection  w4th  the  conjunctival 
sac  should  be  established,  then  the  cutaneous  opening 
is  easily  closed  by  cauterization. 

5.  Dacryops  is  the  term  applied  to  a  bluish,  trans- 
lucent, soft  tumor  which  appears  in  the  upper  and  outer 
conjunctival  fornix.  It  is  caused  by  the  occlusion  of 
one  or  more  of  the  ducts  which  convey  the  lacrymal 
fluid  from  the  gland  into  the  conjunctival  sac.  As  the 
tumor  is  a  distended  duct  filled  with  tears  it  will  collapse 
if  punctured  and  the  treatment  consists  in  establishing 
a  permanent  opening. 

ANOMALIES    OF    THE    PUNCTA    AND    CAXALICULI. 

I.  Eversion,  or  falling  ui  the  lower  punctum  away 
from  the  eyeball,  may  be  due  to  ectropion,  chronic  con- 
junctivitis, blepharitis  marginalis,  lagophthalmia,  or 
the  relaxation  of  the  lower  lid  found  in  old  age. 
Though  the  upper  punctum  may  be  in  its  normal  posi- 
tion, epiphora  will  follow  any  hypersecretion  of  tears. 


90  LESSONS    ON    THE    EYE. 

2.  Obliteration  of  a  punctum  or  canaliculus  may  be 
congenital  or  mav  result  from  traumatism  or  chronic 
inflammation. 

3.  Obstruction  of  a  canaliculus  by  a  foreign  body 
sometimes  occurs. 


Fig.  67. — Weber's  straight  canaliculus  knife. 
CHRONIC    DACRYOCYSTITIS. 

This  is  a  catarrhal  inflammation  of  the  sac  and  duct. 
Stricture  of  the  duct  will  also  be  included  under  this  head 
as  these  conditions  merge  into  each  other  and  are  more 
or  less  interdependent. 

Symptoms. — A  slight  catarrhal  inflammation  of  the 
mucous  membrane  of  the  sac  and  duct  creates  a  muco- 
purulent discharge,  some  of  which  passes  backward 
through  the  puncta  and  produces  a  mild  conjunctivitis 
and  epiphora.  This  slight  attack  may  disappear  with- 
out treatment,  or  upon  the  instillation  of  some  mild 
antiseptic  collyrium  and  the  appropriate  attention  to 
the  nose.  If  the  inflammation  is  more  severe,  the  swell- 
ing of  the  mucous  membrane  will  produce  an  occlusion 
of  the  duct  and  a  consequent  accumulation  of  the  con- 
tents of  the  sac.  The  muco-purulent  contents  will  be- 
come purulent,  and  will  escape  through  the  puncta  and 
excite  a  conjunctivitis.  With  this  conjunctivitis  there 
will  be  hypersecretion  of  tears  and  epiphora.  The  ac- 
cumulation of  fluid  in  the  sac  produces  a  tumefaction 
which  will  disappear  upon  pressure,  as  the  fluid  is  forced 
back  through  the  puncta  or  through  the  stricture  into 
the  nose.     The  stenosis  of  the  duct  may  be  complete. 


DISEASES    OF    THK    LACRYMAL   APPARATUS. 


91 


The  purulent  contents  of  the  cHstended  sac  arc  ex- 
tremely toxic  and  will  almost  surely  infect  a  wound  of 
the  cornea,  will  often  light  up  an  active  inflammation  of 
the  connective  tissue  surrounding  the  sac  (acute  da- 
cryocystitis), and  may,  if  of  long  standing,  i)ro(luce 
caries  of  adjacent  bone. 


Fig.  68. — Slitting  the  canaliculu.s. 


Cause. — Dacryocystitis  may  be  started  by  any  of  the 
numerous  causes  of  inflammation  of  mucous  membrane, 
such  as  temperature  changes  and  infection.  Stricture 
of  the  duct  will  cause  a  dacryocystitis,  and  stricture 
may  be  due  to  morbid  conditions  of  the  nasal  cavities, 
traumatism,  asymmetry  of  the  face,  deflected  septum, 
periostitis  or  syphilis.     The  prognosis  in  chronic  cases 


Q2  LESSONS    ON    THE    EYE. 

is  bad.  If  cured  they  require  months  of  treatment, 
and  too  often  patients  have  not  time  or  inclination  to 
resort  to  the  needed  measures. 

Treatment. — Teach  patients  to  keep  the  sac  empty 
by  pressure.  Have  the  nose  examined  and.  treated  if 
any  morbid  condition  is  found.  Appropriate  attention 
must  be  given  to  any  constitutional  condition,  such  as 
syphiHs  or  struma,  which  may  be  present.  The 
mildest  form  is  sometimes  benefited  by  dropping  into 


Fig.  69.— Bowman's  jMohes  for  dilating  the  nasal  diut. 

the  eye,  three  times  a  day,  a  i  to  2,000  solution  of  blue 
pyoktanin,  or  a  weak  sulfate  of  zinc  or  alum  solution. 
Wash  out  the  sac  with  a  i  to  10,000  solution  of  bichlorid 
of  mercury,  or  a  w^arm  boracic  acid  solution,  every 
other  day.  If  the  discharge  is  purulent,  inject  into  the 
sac  a  small  quantity  of  a  solution  of  nitrate  of  silver 
(gr.  2  to  the  ounce),  protargol  (5  to  20  per  cent.),  or 
argyrol  (10  per  cent.),  after  having  cleaned  it  out  by 
washing  with  bichlorid  of  mercury  or  boracic  acid 
solutions.  If  there  is  a  stricture  of  the  duct  probing 
may  be  necessary.  If  a  canaliculus  must  be  slit  in 
(^rder  to  probe,  sHt  the  upper. 

These  two  procedures,  though  simi)lc,  would  better 


DISKASKS    (J|-     IHK    LACRYIVLAL   APPARATUS. 


93 


be  learned  clinically.  Great  care  must  be  observed 
in  probing,  as  there  is  danger  of  lacerating  the  tissues 
around  the  sac.  This  is  particularly  true  of  the  early 
stages  of  treatment  when  small  probes  are  being  used. 
A  preliminary  injection  of  cocain  into  the  sac  will 
render  the  operation  less  painful.     The  use  of  extract 


of  the  supra-renal  gland,  by  reducing  the  vascularity 
of  the  mucous  membrane  of  the  duct  seems  to  facilitate 
the  passage  of  probes.  When  the  probe  is  removed 
the  sac  and  duct  should  be  treated  with  an  injection  of 
one  of  the  antiseptics  or  silver  preparations  al)ove 
mentioned.  How  often  to  probe,  how  long  to  leave  the 
probe  in  the  duct,  and  the  maximum  size  of  the  probe 
to  be  used  are  questions  upon  which  various  opinions 


94 


LESSONS    ON    THE    EYE. 


are  entertained.     The  author  fa\'ors  small  probes  and 
as  little  use  of  them  as  possible. 

Obstruction   of   the  lacrymal   drainage  is  often  ob- 
served in   the  new-born.     A  weak  zinc  or  silver  solu- 


FlG.  71. — Syringe  for  injecting  the  lacrymal  jjassages. 

tion  will  generally  effect  a  cure.  Surgical  interference 
should  be  postponed  until  all  milder  methods  have 
failed. 

ACUTE    DACRYOCYSTITIS. 

Symptoms. — In  the  course  of  a  chronic  dacryocystitis, 
a  severe  inflammation   may  suddenly  dex'clop  in   the 


DISEASKS    OF    THK    I.ACRVMAL   AFI'ARAIUS.  95 

region  of  the  sac.  There  will  l)e  redness  and  swelling 
which  will  extend  to  the  lids  and  conjunctiva.  Pain 
will  be  very  severe  and  there  mav  be  some  fever.  Pus 
will  form  and  the  skin  oxer  the  ab.scess  become  thin. 
Unless  opened  the  skin  will  break,  emptying  the  con- 
tents of  the  abscess  and  establishing  a  lacrymal  fistula 


Fig.  72. — .\cute  dacryocystitis. 

(Fig.  66).  As  soon  as  the  pus  is  evacuated  the  symp- 
toms rapidly  subside  to  recur  as  soon  as  the  fistula 
is  allowed  to  close. 

Cause. — A  lesion  of  the  mucous  membrane  of  a  sac 
affected  by  chronic  dacryocystitis,  allows  its  toxic  con- 
tents to  infect  the  surrounding  sub-mucous  tissue  and 
the  active  phlegmonous  inflammation  follows. 

Treatment. — Evacuate  the  pus  by  slitting  up  a 
canahculus  if  possible,  if  not  open  through  the  skin  over 


g6  LESSONS    ON    THE    EYE. 

the  sac.  Cleanse  with  some  antiseptic  solution  and  if 
the  swelling  and  pain  are  considerable  use  hot,  antiseptic 
compresses.  Keep  the  incision  open  by  gauze  drain- 
age until  the  abscess  can  be  cleansed  through  a  canal- 
iculus and  then  treat  as  a  chronic  dacryocystitis. 

In  obstinate  cases  of  dacryocystitis  it  is  sometimes 
deemed  expedient  to  completely  obliterate  the  drainage 
passages.  For  example,  a  cataract  operation  should 
never  be  attempted  in  the  presence  of  a  discharge  from 
the  lacrymal  sac,  owing  to  the  imminent  danger  of 
infecting  the  corneal  wound.  The  sac  may  have  to  be 
obliterated  to  stop  the  discharge.  This  is  done  by 
dissecting  it  out  or  destroying  it  with  the  actual  or 
chemical  cautery. 


LESSON   XIII. 

DISEASES  OF  THE  OF^BITS. 

MENINGOCELE. 

Sometimes  there  is  defective  dexelopment  of  the 
bones  of  the  orbital  rim  where  the  nasal  wall  and  roof  of 
the  orbit  unite.  The  result  is  a  congenital,  cystic 
tumor  in  this  region,  composed  of  the  meninges  of  the 
brain,  filled  with  cerebral  fluid.  The  tumor  is  called  a 
meningocele,  or  if  it  contain  brain  substance,  an  en- 
cephalocele.  It  may  be  mistaken  for  an  ethmoidal  muco- 
cele, sebaceous  cyst  or  dermoid  tumor.  The  following 
diagnostic  points  should  be  remembered : 

1.  It  is  congenital. 

2.  It  gives  the  impression  of  being  firmly  attached  to 
the  bone. 

3.  There  is  a  pulsation  of  the  cerebral  fluid  in  a 
meningocele  synchronous  with  the  heart  beat. 

4.  Steady  pressure  will  force  some  of  the  contents  of 
a  meningocele  back  into  the  cerebral  cavity  and  then 
the  opening  in  the  bony  wall  may  be  felt  with  the  point 
of  the  finger. 

5.  Symptoms  of  increased  cerebral  pressure  may  be 
excited  when  the  fluid  is  forced  back  into  the  cerebrum. 

A  meningocele  should  not  be  disturbed. 

PERIOSTITIS. 

Periostitis  may  attack  any  part  of  the  orbit  l)ut  is 
most  frequent  at  the  margin.     When   superficial   the 

7  97 


ge>  LESSONS  on  the  eye, 

hard  swelling  and  tenderness  upon  pressure  make  the 
diagnosis  simpler  than  when  deep  in  the  orbit.  The 
latter  form  is  often  hard  to  differentiate  from  orbital 
cellulitis  until  a  fistula  is  formed  and  rough  bone  can  be 
detected  with  a  probe. 

Symptoms. — Before  entering  upon  the  symptomat- 
ology of  the  few  inflammatory  conditions  to  which 
the  orbit  is  subject,  it  is  well  to  mention  that  there  are  a 
number  of  symptoms  common  to  nearly  all  diseases  of 
the  orbits.  Of  these  there  are  two  so  constantly  in 
attendance  as  to  make  them  worthy  of  special  mention. 

1.  Proptosis  or  exophthalmos. 

2.  Limitation  of  movement  of  the  eyeball. 
Associated  with  these  salient  symptoms  are  diplopia, 

injection  and  chemosis  of  the  conjunctiva,  redness, 
swelling  and  edema  of  the  lids  and  severe  pain,  most 
noticeable  when  the  patient  attempts  to  move  the 
globe,  or  the  surgeon  presses  it  backward  into  the  orbit. 

The  character  of  the  symptoms  in  periostitis  will 
depend  upon  whether  the  inflammation  is  checked  in 
the  stage  of  periosteal  thickening  or  goes  on  to  suppura- 
tion. Also  whether  acute  or  chronic,  circumscribed 
or  diffuse,  external  or  deep-seated. 

When  external  all  the  signs  of  local  inflammation  will 
be  present.  Unless  checked  in  the  first  stages,  pus  will 
form  under  the  skin  and  when  discharged  a  sinus  will 
be  established  through  which  rough  bone  can  be  de- 
tected. The  discharge  keeps  up  for  a  variable  period 
and  when  the  fistula  is  healed  it  leaves  the  characteristic 
funnel-shaped  dimple  in  the  skin,  which  is  adherent  to 
the  underlying  bone.  If  there  is  much  contraction  of 
the  skin  ectropion  results. 


DISEASES    OF    THE    ORBITS.  QQ 

When  deep-seated  and  non-suppuratixe,  the  symp- 
toms will  be  pain  and  probably  protrusion  of  the  ball 
with  some  limitation  of  its  movement.  When  suppu- 
ration takes  place  the  sym])toms  are  j^ractically  those 
of  orbital  cellulitis,  page  loi.  Caries  and  necrosis  mav 
result.  Periostitis  of  the  roof  of  the  orbit  is  the  kind 
most  likely  to  cause  meningitis,  owing  to  the  thinness 
of  the  bone  here  and  the  proximity  of  the  brain. 

Cause. — Injury,  syphilis,  scrofula  and  rheumatism. 
When  syphihtic  it  is  usually  a  tertiary  manifestation. 

Treatment. — The  constitutional  treatment  appro- 
priate to  the  cause  should  be  instituted.  Locally  apply 
hot  compresses,  evacuate  pus  when  formed,  establish 
drainage  and  wash  out  antiseptically.  Correction  of  any 
resulting  deformity  such  as  ectropion  or  lagophthalmia 
should  not  be  attempted  until  the  periostitis  is  entirely 
well. 


CARIES    AND    NECROSIS. 

Caries  and  necrosis  occur  most  frequently  at  the 
margin  of  the  orbit,  owing  to  its  greater  exposure  to 
injury.  They  generally  begin  as  a  periostitis.  The 
course  of  the  disease  is  chronic,  sometimes  covering  a 
period  of  several  years.  A  bad  scar  is  the  usual  result, 
the  skin  contracting  and  adhering  firmly  to  the  under- 
lying bone.  The  danger  of  meningitis  is  greatest  when 
the  horizontal  plate  of  the  frontal  bone  is  the  part 
involved.  The  treatment  consists  in  establishing  good 
drainage  and  cleansing  frequently  with  antiseptic 
injections. 


lOO  LESSONS    ON    THE    EYE. 

HYPEROSTOSIS,    PERIOSTOSIS    AND    EXOSTOSIS. 

Hyperostosis  (thickening  of  bone) ,  periostosis  (thick- 
ening of  the  periosteum),  and  exostosis  (new  bone 
developed  from  the  periosteum) ,  may  occur  in  the  orbit. 
The  symptoms  will  depend  upon  the  extent  and  loca- 
tion of  the  process.  If  of  any  size  exopthalmia  will 
be  noticed.  If  located  near  the  sinuses  at  the  apex, 
the  circulation  in  the  orbit  may  be  interfered  with  or 
pressure  may  be  exercised  upon  the  optic  nerve  or 
nerves  supplying  the  ocular  muscles.  The  treatment 
consists  of  alteratives  internally  or  surgical  removal. 

INJURIES    OF    THE    ORBIT. 

Fractures  may  be  marginal  or  deep-seated.  Deep- 
seated  fractures  may  be  the  result  of  force  applied 
directly  or  indirectly.  There  will  be  hemorrhage  into 
the  orbit  with  protrusion  of  the  ball.  If  the  inner 
wall  is  fractured  blood  will  escape  through  the  nose 
and  air  may  be  forced  into  the  cellular  tissue  of  the 
orbit  and  lids  producing  emphysema.  Direct  fractures 
of  the  roof,  for  example,  from  a  knife  or  cane  are  exceed- 
ingly dangerous  to  Hfe,  owing  to  the  injury  to  the  brain 
which  is  almost  inevitable.  Fractures  extending  into 
the  optic  foramen  are  dangerous  to  \-ision,  owing  to 
direct  injury  to  the  nerve  or  hemorrhage  into  its  sheath. 

The  contents  of  the  orbit  are  subject  to  all  kinds  of 
injuries.  Many  remarkable  cases  have  been  reported, 
showing  the  great  tolerance  of  the  orbital  tissues  to  the 
presence  of  foreign  bodies.  The  following,  reported 
by  Carter,  will  suffice.  A  man  fell  down  a  flight  of 
steps,  at  the  bottom  of  which  was  a  row  of  hat  pegs. 


DISEASES  OF  THE  ORBITS.  lOI 

He  cut  his  eye  lid,  but  did  not  consult  a  surgeon  for  a 
few  days.  The  surgeon  had  treated  him  several  days 
before  noticing  a  foreign  body  in  the  wound.  It 
proved  to  be  the  shaft  of  a  hat  peg  3^  inches  long. 
The  X-ray  is  of  great  value  in  determining  the  presence 
and  location  of  foreign  bodies  in  the  orbit. 

The  treatment  of  all  orbital  injuries  should  be  based 
upon  established  surgical  principles.  In  the  use  of 
antiseptics,  however,  the  sensitiveriess  and  delicacy  of 
the  conjunctiva  and  cornea  must  not  be  overlooked. 

ORBITAL    CELLULITIS. 

This  is  an  inflammation  of  the  cellular  tissue  of  the 
orbit  which  may  be  acute  or  chronic,  but  usually 
results  in  suppuration  with  the  formation  of  an  abscess. 

Symptoms. — Proptosis  with  diplopia,  pain,  limitation 
of  movement  of  the  ball,  injection  and  chemosis  of  the 
conjunctiva  and  sweUing  and  redness  of  the  lids.  As 
the  severity  of  this  disease  varies  greatly  in  different 
cases,  we  shall  expect  variation  in  the  degree  of  mani- 
festations of  all  symptoms.  In  the  severe  forms  there 
will  be  chills  with  fever,  and  may  be  loss  of  vision  due 
to  pressure  upon  the  optic  nerve  or  disturbance  of  the 
intra-ocular  circulation.  There  may  be  ulceration  of 
the  cornea  and  possibly  suppuration  of  the  whole 
eyeball.  Thrombosis  of  the  intra-cranial  venous  si- 
nuses and  meningitis  ha\-e  both  resulted  from  orbital 
suppuration. 

Cause. — The  causes  are  such  as  produce  cellulitis  in 
other  locations  and  are  numerous.  They  may  be 
traumatic    or    idiopathic.     Special    mention    may    be 

flOO  E.  Clinton  /ky%, 


I02  LESSONS    ON    THE    EYE. 

made  of  the  severe  form  due  to  erysipelas,  and  also 
to  the  fact  that  it  may  arise  by  metastasis  in  all 
pyemic  conditions,  or  puerperal  septicemia.  It  may 
follow  thrombosis  of  the  ophthalmic  vein  and  has  been 
known  to  result  from  abscesses  of  the  teeth  in  the 
upper  jaw.  Suppuration  in  the  adjoining  cavities 
(frontal  sinus,  ethmoid  cells  and  sphenoidal  sinus), 
may  extend  to  the  orbit. 


Fig.  73. — Double  orbital  cellulitis,  the  result  of  erysipelas.      (De  Sihweinitz 


Treatment. — Support  with  tonics,  especially  quinin 
and  iron.  Relieve  pain  by  anodynes.  Apply  hot 
fomentation,  and  as  soon  as  the  abscess  can  be  located 
or  any  sign  of  fluctuation  appears,  open  and  treat 
antiseptically.  When  the  exophthalmos  is  very  pro- 
nounced and  the  pain  intense  it  is  advised  to  make  an 
incision  into  the  orbit,  through  the  conjunctiva  without 
waiting  for  evidence  of  suppuration.      In  making  the 


DISEASES    OF   THE    ORBITS.  IO3 

incision   the   flat  side  of   the  knife  sliould   be  (hreeled 
toward  the  ball  and  the  ocular  muscles  avoided. 

Inflammation  of  the  capsule  of  Tenon  has  been  known 
to  occur  without  involving  the  cellular  tissues  of  the 
orbit.  When  idiopathic  it  is  generally  rheumatic  in 
origin  and  the  treatment  should  be  directed  to  that 
dyscrasia.  The  traumatic  form  has  often  been  caused 
by  infection  following  an  operation  upon  the  muscles 
for  the  correction  of  strabismus.  The  treatment  is 
the  same  as  in  orbital  cellulitis. 


TUMORS    OF    THE    ORBIT. 

The  orbit  contains  many  different  tissues,  con- 
sequently a  great  variety  of  tumors  may  develop  in 
this  locality.  Those  which  originate  in  adjoining 
cavities  may  reach  a  large  size  before  any  symptoms 
of  orbital  disease  become  manifest.  It  is  therefore 
well  to  determine,  if  possible,  whether  other  cavities 
are  involved.  When  there  is  an  exophthalmos,  which 
has  developed  slowly,  combined  with  limitation  of 
movement,  without  the  usual  manifestations  of  inflam- 
mation, the  diagnosis  of  a  tumor  may  be  arrived  at 
with  a  degree  of  assurance.  If,  however,  the  tumor 
has  developed  rapidly  and  is  associated  with  symptoms 
of  active  inflammation,  the  differentiation  from  ]X'ri- 
ostitis,  orbital  cellulitis,  etc.,  may  be  difficult. 

If  the  nature  and  extent  of  the  growth  will  admit,  it 
should  be  removed  without  the  ball.  To  accomplish 
this  it  may  be  necessary  to  temporarily  resect  a  wedge- 
shaped  piece  of  the  outer  orbital  wall.  When  the 
tumor  is  malignant   the  most  radical  removal  of  eye- 


I04  LESSONS    ON    THE    EYE. 

l)all  and  orbital  contents  secures  no  immunity  from  a 
probable  recurrence. 

PULSATING    EXOPHTHALMOS. 

This  condition  may  develop  slowly  but  its  onset  is 
usually  sudden.  The  patient  may  be  conscious  of  a 
rupture  or  giving  way  of  some  structure  in  the  head. 
This  sensation  is  soon  followed  by  protrusion  of  the 
ball,  congestion  of  the  conjunctiva,  swelling  of"  the  lid, 
pain,  pulsation  of  the  eyeball,  and  a  bruit  heard  over 
the  orbital  region.  If  firm  pressure  is  applied  over 
the  eye  it  can  be  forced  back  into  its  normal  position. 
When  back  the  bruit  may  no  longer  be  heard  and  the 
roaring  sound,  so  annoying  to  the  patient,  generally 
ceases.  Sometimes  vision  is  much  impaired  and  the 
ophthalmoscope  shows  a  swelling  of  the  optic  disc  with 
distortion  and  enlargement  of  the  retinal  veins. 

Cause. — It  is  generally  due  to  rupture  of  the  internal 
carotid  artery  within  the  cavernous  sinus.  It  may  be 
traumatic  or  spontaneous.  If  the  latter  there  must 
ha\'e  been  a  diseased  condition  of  the  artery  which 
thinned  its  walls.  Aneurism  of  the  ophthalmic  artery 
is  sometimes  the  cause. 

Treatment. — The  object  of  treatment  is"  to  establish 
a  clot  in  the  ruptured  artery.  Compression  of  the 
common  carotid  should  be  tried.  Digital  or  instru- 
mental pressure  should  be  exerted,  for  as  much  of  the 
time  of  each  day  as  the  patient  can  endure  it.  If  this 
fail,  ligation  of  the  common  carotid  must  be  resorted  to. 
If  the  patient  escapes  the  dangers  incident  to  this 
operation  the  pulsating  exophthalmos  will  usually  be 
found  cured. 


LESSON  XIV. 

DISEASES  OF  THE  C(3NJUNCTI VA. 

CATARRHAL    CONJUNCTIVITIS. 

This  is  the  most  frequent  disease  of  the  eye.     It 
usually   attacks   both  eyes,  varies  greatly  in  severity 

and    duration,    and    lends    to    spontaneous    recoverv, 


I'"iG.  74. — Conjunclival  congestion.     The  circumcorneal  zone  the  last  jiart  to 
become  injected. 

rarely  lasting  o\'er  two  weeks.  Hyperemia  of  the  con- 
junctiva is  generally  given  as  a  separate  disease,  but 
practically  differs  from  simple  catarrhal  conjunctivitis 
only  in  degree,  being  milder. 

105 


I06  LESSONS    ON    THK    EYK. 

Sy)upto)us. — 1.  Congestion  of  the  palpebral  and 
ocular  conjunctiva,  the  pericorneal  zone  remaining 
normal  or  the  last  part  to  become  red.      (Fig.  74.) 

2.  Pain  of  a  scratchy,  burning  kind,  feeling  often  as 
if  there  was  a  foreign  body  under  the  Hds. 

3.  Vision  slightly  diminished  owing  to  the  presence 
of  mucus  and  pus  on  the  cornea. 

4.  Discharge  of  a  muco-purulent  nature  which  mats 
the  lashes  into  small  bundles  and  sticks  the  lids  to- 
gether during  sleep. 

5.  Photophobia  or  intolerance  of  light. 

6.  Swelling  of  the  lids  (slight)  and  some  thickening 
of  the  conjunctiva. 

Cause. — Foul  atmosphere,  dust,  smoke,  wind,  heat, 
cold,  the  glare  of  the  sun,  and  errors  of  refraction. 
The  exanthematous  fevers,  diseases  of  the  lacrymal 
sac  and  duct,  nasal  catarrh  and  hay  fever.  A  very 
contagious  form  of  catarrhal  conjunctivitis,  w^hich  at 
times  becomes  epidemic,  is  caused  by  a  small  bacillus 
described  by  Weeks,  and  a  conjunctivitis  clinically 
very  similar  to  that  produced  by  the  Weeks  bacillus 
is  due  to  the  pneumococcus.  Also  a  mild  but  per- 
sistent form  of  catarrhal  conjunctivitis  is  associated 
with  the  presence  of  the  diplo-bacillus  of  Morax  and 
Axenfeld. 

Treatment. — Remove  the  cause  if  discovered.  Rest 
eyes  and  keep  them  clean.  Use  a  cold  compress  as 
follows : 

Acidi  borici 5^ 

Tinctura:  opii  deodorat^c 3vi 

Aqme   destellatiu,    (].    s.  ft.    .    .    .   o\'^^i 


DISEASES    OF    THE    CONJUNCTIVA.  I07 

This  is  to  be  applied  to  the  outside  of  the  closed  lids, 
on  a  thin  cloth,  folded  once  or  twice,  for  fifteen  minutes 
at  a  time,  four  times  a  day.  The  solution  should  be  ice 
cold  when  used  and  the  wet  cloths  changed  every 
minute.  Apply  a  weak  yellow  oxid  of  mercury  oint- 
ment or  boric  acid  salve  to  the  edge  of  the  lids  at  night 
to  prevent  adhesion.  If  discharge  is  profuse  or  ])uru- 
lent,  paint  everted  lids,  once  a  day,  with  a  solution  ot 
nitrate  of  silver,  one  to  two  grains  to  the  ounce,  or  a 
2  to  5  per  cent,  solution  of  protargol.  One  drop  of  a 
10  per  cent,  solution  of  argyrol,  three  or  four  times  a 
day,  is  often  very  beneficial.  Argyrol  is  painless  and 
practically  non-irritating.  A  fresh  solution  should  be 
used.  Astringent  collyria  containing  sulfate  of  zinc, 
tannin,  alum,  etc.,  are  very  popular.  They  are  capable 
of  mischief  if,  through  an  error  of  diagnosis,  they  are 
used  in  iritis,  cyclitis  or  acute  keratitis.  An  exception 
should  be  made  of  the  diplo-bacillus  conjunctivitis,  in 
which  form  zinc  acts  as  a  specific. 

CHRONIC    CATARRHAL    CONJUNCTIVITIS. 

Symptoms. — After  the  subsidence  of  an  acute  attack 
the  same  general  symptoms  may  persist  in  a  milder  form 
or  they  may  develop  slowly  without  an  acute  manifest- 
ation. In  the  chronic  form  the  palpebral  conjuncti\-a 
and  the  fornix  are  the  parts  chiefly  involved. 

Cause. — The  same  agents  which  produce  acute 
catarrhal  conjunctivitis,  but  especially  those  which  are 
slow  and  continuous  in  their  action. 

Treatment. — The  source  of  any  chronic  irritation 
should  be  removed  and  the  same  line  of  treatment 


Io8  LESSONS    ON    THE    EYE. 

as  recommended  for  an  acute  attack  instituted. 
Stronger  remedies  are  more  applicable  to  the  chronic 
form,  and  zinc,  alum,  argyrol,  nitrate  of  silver,  protar- 
gol  or  sulfate  of  copper  may  be  used.  Caution  shotild 
be  observed  in  the  continuous  use  of  the  silver  prepa- 
ration sowing  to  the  danger  of  producing  a  dark,  muddy 
discoloration  of  the  conjunctiva  called  argyria. 

PURULENT    CONJUNCTIVITIS. 

This  condition  may  be  divided  into  two  forms:  i. 
The  infantile  variety  or  Ophthalmia  Neonatorum,  which 
arises  between  the  third  and  eighth  day  after  birth 


Fig.  73. — Purulent  conjunctivitis. 

and  generally  attacks  both  eyes.  2.  The  adult  variety, 
or  Gonorrheal  Ophthalmia,  which  may  attack  but  one 
eye. 

Symptoms. — The  period  of  incubation  varies  from  6 
to  60  hours.  The  disease  may  be  divided  into  three 
stages:  Stage  of  infiltraticm,  which  lasts  from  3  to  6 
days;  stage  of  pyorrhea,  which  lasts  from  3  to  ()  weeks, 


J)Isf:asks  of  thk  conjunctiva.  log 

and  stage  of  chronic  blennorrhea,  which  varies  greatly 
in  duration. 

r.  Congestion  of  the  palpebral'and  ocular  conjunctiva. 

2.  Pain  is  severe  and  of  a  smarting,  burning  variety. 
The  great  thickness  and  weight  of  the  lids  causes  also  a 
continuous  dull  ache  in  the  eye. 

3.  Discharge  is  profuse  and  of  a  thin  ichorous,  beef 
juice  kind  in  the  first  stage  which  changes  in  the  second 
to  thick  yellow  pus. 

4.  Swelling  of  the  lids  is  so  intense  as  to  interfere 
with  the  proper  inspection  of  the  eye.  When  the  pus 
begins  to  flow  freely  this  swelling  usually  decreases. 
The  conjunctiva  becomes  so  edematous  (chemosis) 
as  to  ox'erlap  the  circumference  of  the  cornea. 

5.  Vision  may  be  interfered  with  by  the  pus  on  the 
cornea,  by  corneal  ulceration,  or  bv  the  inabilitv  to 
raise  the  upper  lid. 

6.  Ulceration  of  the  cornea,  the  result  of  disturbed 
nutrition  and  infection,  may  supervene.  This  is  the 
most  dangerous  symptom  owing  to  the  possibility  of 
permanent  scars,  intra-ocular  infection,  and  panoph- 
thalmitis. 

Cause. — Inoculation  with  gonorrheal  ^•irus,  the 
gonococcus  of  Neisser  being  found  in  the  discharge. 
There  are  mild  types  which  clinically  simulate  purulent 
conjunctivitis  in  which  the  gonococcus  cannot  be 
demonstrated.  If  the  gonococcus  is  absent  in  the 
infantile  variety,  the  disease  has  been  caused  by  a  vagi- 
nal discharge  other  than  gonorrheal.  Such  cases  are 
usually  mild.  If  the  gonococcus  is  absent  in  the  adult 
form,  the  disease  must  be  due  to  other  pus-producing 
germs.     It    will    sometimes    follow    mechanical    and 


no  LESSONS    ON    TOE    EYE. 

chemical  accidents  or  badly  treated  catarrhal  conjunc- 
tivitis. A  microscopic  examination  of  the  secretion 
should  always  be  made. 

Treatment. — In  the  stage  of  infiltration  cold  applica- 
tions must  be  kept  on  the  eye  continuously.  This  may 
be  done  by  keeping  a  number  of  small  squares  of  muslin 
on  a  block  of  ice,  and  transferring  one  to  the  eye  every 


Fig.  76. — Desmarre's  lid  elevator. 

minute.  However,  judgment  must  be  exercised  in  the 
application  of  cold  as  it  is  a  well-known  fact  that  the 
puny  and  scrofulous  bear  it  badly.  The  secretion 
should  be  washed  away  with  a  warm  boric  acid  solu- 
tion (3  per  cent.) ,  or  some  other  mild  antiseptic,  about 
once  every  hour  or  oftener.  The  bowels  should  be 
well  purged  with  salines  and  the  patient  kept  as  quiet 
as  possible.  If  pain  is  very  severe  an  adult  may  be 
given  an  anodyne.  In  the  stage  of  pyorrhea  the 
mechanical  cleansing  of  the  conjunctiva  must  be 
vigorously  continued,  but  the  greatest  care  must  be 
taken  not  to  injure  the  corneal  epithelium.  The 
upper  lid  should  be  turned  once  a  day  and  its  conjunc- 
tival surface  painted  with  a  i  per  cent,  solution  of 
nitrate  of  silver.  In  the  place  of  nitrate  of  silver  one 
of  the  less  irritating  silver  preparations  may  be  used. 
Protargol  solution  (5  to  20  per  cent.)  or  argyrol  solu- 
tion (10  to  25  per  cent.)  may  be  dropped  between  the 
lids  every  one  or  two  hours.  Argyrol  is  practically 
non-irritating   and   is   probably    the   best   remedy   we 


DISEASES    OF    THE    CONJl'XCTIVA.  I  I  I 

ha\-c'.  lM\'(iucnt  irrisj;ali(>n  with  a  i  lo  5,000  solution 
of  permanganate  of  potash  is  highly  recommended. 
If  the  swelling  of  the  lids  is  so  great  as  to  prevent 
eversion  or  to  endanger  the  circulation,  the  outer 
canthus  should  be  slit  with  a  pair  of  scissors  (canthot- 
omy).  In  the  second  stage  ccjld  applications  should 
be  diminished,  if  not  altogether  discontinued,  owing 
to  their  depressing  influence  upon  the  nutrition  of  the 
cornea.     If  the  cornea  becomes  hazy  or  shows  a  spot  of 


Vu;.  77. — .\pplicatiun  ni  Huller's  shield.      (De  Schweinitz.) 

ulceration  the  general  treatment  for  corneal  ulcers 
(page  140)  may  be  followed  as  closely  as  is  possible 
under  the  circumstances.  In  the  third  stage  of  the 
disease  the  treatment  advised  for  chronic  catarrhal 
conjunctivitis   (page   107)   should  be  followed. 

In  adults,  where  one  eye  is  affected,  protect  the  good 
eye  by  covering  it  with  a  watch  crystal  held  in  position 
by  adhesive  plaster.  This  is  called  Buller's  shield. 
As  the  secretion  is  most  liable  to  get  into  the  good  eye 


LESSONS    ON    THE    EYE. 


by  flowing  across  the  root  of  the  nose,  the  shield  should 
be  well  sealed  at  this  point  by  the  use  of  cotton  and 
collodium.  To  prevent  ophthalmia  neonatorum  in  a 
child  born  of  a  diseased  mother,  resort  to  the  method 
of  Crede,  which  is  to  wash  its  eyes  thoroughly  just  after 
birth  and  drop  between  the  lids  several  drops  of  a  five 
grain  to  the  ounce  solution  of  nitrate  of  silver.  Crede 
advised  a  ten  grain  to  the  ounce  solution,  but  this  has 
proved  unnecessarily  strong.  There  is  reason  to  be- 
lieve that  argyrol  or  protargol,  in  the  proper  strength, 
may  be  as  efficient  prophylactics  as  the  nitrate  of 
silver. 

There  is  a  law  in  many  States  punishing  midwives 
and  nurses  for  not  immediately  reporting,  to  a  health 
officer,  the  appearance  of  inflammation  in  the  eyes  of 
a  new-born  under  their  care.  A  few  convictions  under 
this  law  would  materially  lessen  the  blindness  from 
ophthalmia  neonatorum. 

MEMBRANOUS    CONJUNCTIVITIS. 

The  characteristic  feature  of  this  inflammation  is  a 
plastic,  fibrinous,  pseudo-membrane  on  the  tarsal  and 
sometimes  on  the  ocular  conjunctiva.  With  the  excep- 
tion of  this  membrane  the  symptoms  are  very  similar 
to  those  of  purulent  conjunctivitis.  It  is  customary  to 
divide  this  affection  into  croupous  and  diphtheritic 
conjunctivitis,  but  since  the  disease  appears  in  every 
degree  of  severity,  from  an  almost  harmless  condition 
to  one  of  a  most  destructive  character,  it  is  difficult  to 
draw  a  dividing  line  clinically.  Microscopic  examina- 
tion of  the  secretion  should  be  made  at  once.     The 


DISEASES    OF    THE    CONJUNCTIVA.  II3 

pneumococcus,  streptococcus,  staphylococcus  or  Klebs- 
Loeffier  bacillus  will  generally  be  found.  vSome  of  the 
most  destructive  cases  reported  ha\'e  been  due  to 
streptococcus  infection. 

Symptoms.— I.  Congestion  of  the  conjunctival  vessels 
is  hidden  by  the  plastic  membrane  in  severe  cases.  In 
a  mild  case,  the  plastic  membrane  being  confined  to 
the  lids,  the  ocular  conjunctiva  will  appear  injected. 

2.  Pain  is  generally  of  an  itching,  burning  character, 
but  when  there  is  great  sweUing  of  the  lid  there  is  an 
added  sensation  of  pressure  on  the  ball. 

3.  Discharge  is  at  first  serous  and  flaky,  and  may  be 
tinged  with  a  little  blood.  As  soon  as  the  membrane 
begins  to  soften  the  discharge  becomes  purulent. 

4.  Swelling  of  the  lids  is  almost  imperceptible  in  the 
mild  forms  but  in  a  severe  case  the  upper  lid  may 
l)ecome  so  thick  and  tense  as  to  render  its  eversion 
impossible.  The  exudation  into  the  conjunctiva  may 
be  so  excessive  as  to  shut  off  the  circulation,  producing 
gangrene  and  subsequent  cicatricial  contraction  and 
adhesions. 

5.  Vision  is  affected  as  in  purulent  conjunctivitis 
(page  109). 

6.  Ulceration  of  the  cornea  is  produced  as  in  purulent 
conjunctivitis  (page  109).  In  mild  attacks  it  rarely 
happens  but  in  severe  cases  it  is  almost  inevitable. 

7.  The  membrane  in  mild  cases  is  limited  to  the  palpe- 
bral conjunctiva  and  can  be  mped  off  leaving  a  slightly 
bleeding  surface.  In  severe  cases  it  covers  the  entire 
conjunctiva  and  can  only  be  removed  by  force,  leaving 
a  raw  surface. 

8.  Constitutional  symptoms  will  be  ])resent  when  the 


114  LESSONS    ON    THE    EYE, 

disease  is  diphtheritic,  and  in  severe  cases  due  to  other 
infections. 

Cause. — This  must  be  determined  by  the  microscopic 
findings. 

Treatment. — For  mild  cases  follow  the  treatment 
recommended  for  catarrhal  conjunctivitis  (page  io6) 
being  careful  though  not  to  use  nitrate  of  silver  until 
the  membrane  has  disappeared.  Before  the  separa- 
tion of  the  membrane  cleansing  the  conjunctival  sac 
three  or  four  times  a  day  with  an  antiseptic  solution 
(bichlorid  i  to  5,000)  is  advised.  In  the  severe  form 
follow  the  treatment  as  suggested  for  purulent  conjunc- 
tivitis (page  no)  except  that  cold  applications  must 
not  be  used  as  continuously  owing  to  greater  danger 
of  depressing  the  circulation,  and  nitrate  of  silver  must 
be  applied  with  caution  and  then  not  until  the  mem- 
brane has  been  thrown  off.  If  the  diphtheritic  bacillus 
can  be  demonstrated  constitutional  treatment,  includ- 
ing anti-toxin  injections,  should  be  instituted  at  once. 


LESSON  XV. 

DISEASES  OF  THE  CONJUNCTIVA 

(Continited). 

GRANULAR    CONJUNCTIVITIS    OR    TRACHOMA. 

The  characteristic  feature  of  this  disease  is  hyper- 
trophy of  the  conjunctiva  and  the  appearance  in  that 
membrane  of  small  granular  bodies.  Trachoma  may 
assume  three  forms : 

I.  Papillary  trachoma  in  which  the  characteristic 
feature  is  hypertrophy  of  the  conjunctiva.  The  nor- 
mal   papillct?   are  greatly  increased  in  size,  hence  the 


Fig.  78. — Granular  upper  lid.     a,   Granulations;  b,  line  of  scar,  in  typical 
position  parallel  with  border  of  lid.      (Nettleship.) 

name.  This  form  is  also  called  chronic  conjunctival 
blennorrhea,  as  there  is  always  a  variable  amount  of 
pus  in  the  discharge.  Notwithstanding  the  absence 
of  the  trachoma  follicles  the  conjunctiva  undergoes 
cicatricial  changes  and  the  sequellae  are  practically  the 
same  as  when  the  granules  are  present. 

2.  Granular   trachoma   in   which    the   characteristic 
feature  is  the  appearance  in  the  conjunctiva  of  small 
IIS 


ii6 


LESSONS    ON    THE    EYE. 


follicles  or  granules.  These  follicles  are  composed  of 
lymphoid  cells  and  connective-tissue  cells  surrounded 
by  an  ill-defined  fibrous  capsule.  They  are  imbedded 
in  the  fibrous  layer  and  have  a  yellowish  or  grayish 
appearance.  They  develop  later  into  connective  tissue 
which  undergoes  cicatricial  contraction.  The  follicles 
are  most  numerous  in  the  fornix,  but  may  be  found  in 
any  part  of  the  palpebral  conjunctiva. 


KiG.  yg. — Exuberant  gramildtions.     No  indications  of  i  icalri/.ation  are  pres- 
ent.     (Jones.) 


3.  Mixed  trachoma,  which  is  the  form  under  which  we 
generally  see  the  disease,  is  a  combination  of  the  two 
preceding  varieties. 

Symptoms. — The  eyes  are  irritable,  giving  distress 
under  exposure  or  misuse.  The  lids  may  be  swollen, 
and  may  droop  a  little.  There  is  a  slight  muco-puru- 
lent  or  purulent  discharge  and  there  is  a  scratchy  feel- 
ing under  the  lids.  Upon  inspection  of  the  palpeliral 
conjunctiva   the  characteristic   appearance   abo\-e  de- 


DISEASES    OF    THE   CONJUNCTIVA.  II 7 

scribed  will  bo  found.  It  the  disease  is  of  the  papillary 
form  the  conjunctiva  will  have  a  rough  or  velvety  ap- 
pearance due  to  the  enlarged  papilhe  and  the  color  of  the 
swollen  conjuncti\-a  is  of  a  slightly  bluish  tinge.  There 
will  also  be  some  pus  in  the  conjunctival  fornix.  If 
the  disease  is  of  the  granular  form  the  peculiar  follicles 
will  be  present,  but  as  stated  above  the  usual  picture  is 
a  combination  of  these  varieties.     With  the  progress  of 


Fig.  80.— Trachoma  and  pannus.     (Berry.) 

the  disease  all  the  symptoms  increase  in  severity. 
Cicatricial  changes  will  take  place  in  the  conjunctiva 
and  even  in  the  underlying  tarsus,  rendering  the  mucous 
membrane  hard  and  fibrous  in  ])arts  and  by  its  contrac- 
tion bending  the  tarsus  so  as  to  produce  trichiasis  and 
its  attendant  evils.  The  ocular  conjunctiva  will  be- 
come injected  and  pannus  will  develop  (page  143). 
Ulceration  of  the  cornea  is  a  frequent  complication  and 
iritis  may  occur.  Trachoma  exhibits  a  marked  tend- 
ency toward  remissions  and  relapses.  As  a  rule,  the 
disease  covers  a  period  of  years  unless  persistently  and 


Il8  LESSONS    ON   '1"HE    EYE. 

successfully  treated.     Some  cases  seem  incurable;  they 
will  relapse  until  vision  is  practically  destroyed. 

Cause. — Trachoma  is  generally  conceded  to  be  con- 
tagious, and  the  principle  of  the  contagium  is  supposed 
to  be  a  micro-organism.  Numerous  trachoma  germs 
have  been  described,  but  none  of  them  has  as  yet  been 
accepted  as  the  specific  cause  of  the  disease.  The  fact 
that  one  eye  may  be  affected  for  years  without  infect- 
ing its  fellow  is  adduced  as  an  argument  against  the 
contagious  theory.  The  tendency  of  the  disease  to 
spread  in  crowded  institutions  is  in  favor  of  this  theory. 
Certain  races,  among  which  are  the  Jews  and  the  Irish, 
show  a  predisposition  to  trachoma,  whereas  the  negro 
of  our  Southern  States  is  almost  immune. 

Treatment. — Nitrate  of  silver,  five  grains  to  the  ounce, 
applied  to  the  conjunctiva  of  the  everted  upper  lid, 
once  a  day  or  every  other  day,  depending  upon  the 
effect,  is  a  valuable  remedy.  When  nitrate  of  silver 
is  appHed  to  the  conjunctiva  a  white  coagulum  is  at 
once  formed.  The  amount  and  rapidity  of  the  forma- 
tion of  this  coagulum  indicates  the  activity  of  the 
remedy.  When  the  effect  desired  has  been  gotten 
the  action  of  the  silver  should  be  checked  by  a  few  drops 
of  a  solution  of  common  salt.  During  the  above  ap- 
plication the  cornea  should  be  protected  as  much  as 
possible.  Bichlorid  of  mercury  solution  (i  to  5,000), 
protargol  (20  per  cent.)  and  argyrol  (25  per  cent.), 
are  all  useful  agents.  They  should  be  applied  directly 
to  the  conjunctiva  of  the  upper  lid.  Rubbing  them 
into  the  membrane  with  more  or  less  force,  by  means  of 
a  cotton  appHcator,  has  been  recommended.  These 
remedies  are  particularly  applicable  to  the  treatment 


DISEASES    OF    THE    CONJUNCTIVA.  II9 

of  papillary  trachoma.  For  cases  in  which  the  f(  )llicular 
feature  predominates,  the  sulfate  of  copi)er,  la])is 
divinus  or  alum  stick  is  the  best  remedy.  This  should 
be  apphed  hghtly  or  thoroughly,  daily  or  with  longer 
intervals,  depending  upon  the  effect  in  each  case.  In 
mixed  cases  it  is  well  to  first  reduce  the  papillary  swell- 
ing with  nitrate  of  silver,  argyrol  or  bichloride  of 
mercury,  and  then  treat  the  granular  trachoma  with 
bluestone.  Cold  applications  are  often  soothing  and 
beneficial.  In  the  late  cicatricial  stages  ointment  of 
yellow  oxid  of  mercury  (grains  iv  to  the  ounce)  or 
corrosive  sublimate  (gr.  1/20  to  the  ounce)  are  recom- 
mended. Boroglycerid  (30  per  cent.)  and  glycerolc  of 
tannin  (5  to  25  per  cent.)  may  be  tried.  For  cases 
which  cannot  be  seen  regularly.  Prince  recommends 
copper  sulfate  in  glycerin,  six  grains  to  the  dram. 
A  solution  consisting  of  one  drop  of  this  to  twenty  drops 
of  water  should  be  made  fresh  every  morning.  Of  the 
diluted  solution,  one  drop  should  be  instilled  into  the 
eye  three  times  a  day. 

Where  the  appearance  of  the  granules  indicates  its 
feasibihty,  squeezing  them  out  with  Knapp's  roller 
forceps  facihtates  the  cure.  This  should  be  thoroughly 
done  under  an  anesthetic,  and  the  hds  subsequently 
treated  with  argyrol  or  bichlorid  of  mercury  solutions. 
Old  cases,  in  which  there  is  considerable  pannus,  as 
shown  in  Fig.  80,  are  often  greatly  improved  by  the  use 
of  an  infusion  of  jequirity.  The  cases  on  which  jequir- 
ity  is  used  should  be  carefully  selected  and  as  its  use  is 
sometimes  attended  with  danger,  this  treatment  should 
be  left  to  an  oculist.  The  use  of  jequirity  or  its  substi- 
tute jequiritol  will  sometimes  cause  dacryocystitis. 


I  20  LESSONS    ON    THE    EYE. 

ACUTE    TRACHOMA. 

During  the  course  of  a  clironic  trachoma  the  diseased 
eyes  may  take  on  a  se\-erc  acute  inflammation  or  the 
disease  may  seem  to  originate  with  an  acute  attack. 
Such  an  inflammation  is  spoken  of  as  acute  trachoma, 
hut  is  in  reahty  a  case  of  chronic  trachoma  plus  an 
acute  conjunctivitis. 

Symptoms. — Rapid  swelHng  of  the  hds  and  hyper- 
trophy of  the  conjunctiva.  Pain,  which  may  extend 
to  the  brow  and  temples,  lacrymation,  heat,  photopho- 
bia and  congestion,  with  a  muco-purulent  discharge. 
The  palpebral  conjunctiva  is  swollen,  red  and  shiny. 


I 


Si. — Knapp's  roller  forceps. 


The  translucent  granules,  that  are  covered  by  the 
hypertrophied  epithelium,  usually  are  not  seen  until  the 
acute  symptoms  subside.  This  occurs  in  from  one  to 
three  weeks.  It  will  often  be  impossible  to  distinguish 
this  disease  from  acute  catarrhal  conjunctivitis  until 
the  granules  appear. 

Treatment. — Apply  iced  compresses  or  the  cold  boric 
acid  and  tincture  of  opium  solution  recommended  on 
page  1 06.  Ten  per  cent,  argyrol  solution  may  be  of 
service.  Distress  will  sometimes  be  so  great  as  to 
warrant  the  use  of  bromids  or  morphin.  When  the 
swelhng  and  pain  have  subsided  and  the  granules 
appear,  treat  as  a  case  of  chronic  trachoma. 


DISEASES    OF    THE    CONJUNCTIVA.  121 

FOLLICULAR    CONJUNCTIVITIS. 

This  disease  is  sometimes  deseriVjed  as  a  form  of  tra- 
choma, as  they  are  frequently  almost  identical  in  ap- 
pearance. That  there  is  a  distinct  difference  is  proven 
by  the  fact  that  follicular  conjunctivitis  never  perma- 
nently injures  the  conjunctiva,  whereas  trachoma  al- 
ways does. 

Symptoms. — The  symptoms  are  those  of  an  acute  or 
chronic  catarrhal  conjunctivitis  to  which  is  added  the 
appearance  of  the  follicles  in  the  fornix  of  the  lower  lid, 


Fu;.  S2.— Follicular  lonjunc  tivitis.      (After  Klilc.) 

rarely  in  the  upper  lid.  These  granules,  about  the  size 
of  a  pin  head,  are  comp(ised  of  adenoid  tissue,  identical 
with  that  of  the  true  trachoma  follicle.  They  may  be 
few  in  number  or  very  numerous;  if  the  latter,  they 
are  usually  arranged  in  longitudinal  rows.  The  disease 
is  most  frequent  in  children  and  young  people  and  is 
very  prolonged  and  ol;)stinate  in  its  course.  At  times 
it  gives  so  little  annoyance  that  its  presence  is  dis- 
covered by  accident. 

Cause. — The  etiology  is  obscure.  It  is  supposed  to 
be  contagious  as  so  many  of  the  inmates  of  schools  and 
institutions  are  attacked  at  the  same  time.  Bad 
hygienic  surroundings  seem  to  be  factors  in  the  produc- 
tion of  the  disease. 


122  LESSONS    ON    raE    EYE. 

Treatment. — The  same  treatment  as  advised  for 
acute  or  chronic  catarrhal  conjunctivitis  is  appUcable. 
An  ointment  of  acetate  of  lead  (gr.  i  to  5i)  is  recom- 
mended, but  acetate  of  lead  must  never  be  used  if  there 
is  any  implication  of  the  cornea.  If  the  folHcles  are 
prominent,  expression  with  the  roller  forceps  will 
hasten  the  cure.  Fresh  air,  good  food,  proper  exercise, 
attention  to  refractive  errors  and  the  proper  use  of  the 
eves  must  not  be  overlooked. 


LESSON  XVI. 

DISEASES  OF  THE  CONJUNCTIVA 

(Continued). 

VERNAL    CONJUNCTIVITIS,    OR    SPRING    CATARRH. 

This  is  a  disease  of  childhood  or  early  youth.  It 
affects  both  eyes  and  comes  on  with  the  advent  oi 
warm  days  (hence  the  name),  and  will  frequently  last 
until  cold  weather.  There  is  a  tendency  to  recurrence 
in  the  same  individual  year  after  year.  The  attacks, 
however,  gradually  cease  and  no  injurious  sequelae 
are  left. 

Symptoms. — The  palpebral  conjunctiva  will  be  hy- 
peremic  and  the  swollen  papillce  assume  a  flattened, 
rectangular  shape.  Frequently  it  appears  to  be  over- 
laid by  a  bluish  white  film  as  if  covered  by  a  thin  layer 
of  milk.  The  ocular  conjunctiva  is  usually  hyperemic 
and  in  typical  cases  presents  a  narrow  band  of  gray 
hypertrophied  tissue  at  the  limbus.  This  swollen 
mass  may  appear  at  the  inner  and  outer  side  of  the 
cornea  or  may  entirely  encircle  it. 

Frequently  it  forms  an  arch  over  the  upper  half  of  the 
cornea.  The  thickened  tissue  is  sometimes  interrupted 
at  intervals  by  depressions  which  give  it  a  nodular  or 
bead-like  appearance.  It  usually  encroaches  upon  the 
cornea  for  a  slight  distance.  The  objective  symptoms 
may  be  Hmited  to  the  changes  in  the  tarsal  conjunctiva 
(60  per  cent.)  or  the  circumcorneal  hypertrophy  may 
123 


124  LESSONS    Ox\    THE    EYE. 

1)0  the  only  oljjective  manifestation  (lo  per  cent.),  but 
a  large  number  of  cases  ^vill  present  involvement  of 
both  (30  per  cent.)- 

The  subjective  symptoms  are  a  pricking  pain,  itching, 
heaviness  of  the  lids,  photophobia  and  some  lacrymation. 

Treatment. — No  remedy  has  yet  been  found  of 
unquestioned  service.  Protection  of  the  eyes  from 
dust  and  wind  and  the  use  of  dark  glasses  must  be 
enjoined.  The  cold  application  on  page  106  will  be 
found  comforting.  The  yellow  oxid  of  mercury  oint- 
ment may  be  tried.  An  ointment  of  salicylic  acid, 
2  per  cent.,  rubbed  into  the  conjunctiva  once  a  day 
has  been  recommended.  This  treatment  should  be 
preceded  by  a  drop  of  cocaine  solution.  One  part  of 
dilute  acetic  acid  to  250  of  water  is  said  to  relieve  the 
pricking  pain.  The  X-ray  has  seemed  to  cure  some 
cases.     Zinc,  alum  and  ichthyol  are  recommended. 

PTERYGIUM. 

This  is  a  triangular  mass  of  hypertrophied  con- 
junctiva, the  apex  of  which  encroaches  upon  the  cornea, 
with  the  base  generally  toward  the  inner,  sometimes 
toward  the  outer  canthus.  In  rare  instances  an  eye 
may  have  two  pterygia,  one  on  each  side.  The  head 
or  apex  is  firmly  united  to  the  cornea,  sometimes  going 
deep  enough  to  destroy  the  membrane  of  Bowman.  A 
pterygium  rarely  grows  beyond  the  center  of  the  cornea 
and  usually  it  requires  years  for  the  apex  to  reach  that 
point.  While  progressing  a  pterygium  is  red,  fleshy 
and  vascular  (p.  crassum),  later,  development  ceases 
and  it  becomes  thin,  white,  membranous  and  more  or 
less  bloodless  (p.  tenuis).     It  affects  vision  by  growing 


DISEASES    OF    THE    CONJUNCTIVA.  I25 

in  front  of  the  pupil  or  by  traction  producing  astig- 
matism. 

Cause. — It  is  found  usually  in  those  whose  eyes  are 
subjected  to  the  irritation  of  wind  and  weather.  Fuchs 
claims  it  is  developed  from  a  pinguecula,  others  main- 
tain that  its  starting-point  is  an  erosion  of  the  corneal 
limbus.      La\'men  ^^"ill  usuallv  call  this  growth  cataract. 


I'"i<"..  83. — Pteryj^iuni.     C,  caruncle;  P,  punctum;  S,  probe  passed  under  the 
upper  margin.     (Fuchs.) 

Treatment  is  operative.  False  pterygiiiui  partakes 
of  the  character  of  a  symblepharon.  It  is  an  in- 
flammatory adhesion  of  the  ocular  conjunctiva  to  a 
denuded  or  ulcerated  point  of  the  corneal  limbus 
which  is  the  result  of  acute  blennorrhea,  diphtheria, 
burns  or  injury.  It  can  be  differentiated  from  true 
pterygium  by  its  history,  the  fact  that  it  may  appear 
at  any  point  on  the  circumference  of  the  cornea,  and 
that  it  has  no  tendency  to  progress. 

PINGUECULA. 

This  is  a  small  yellow  elevation  in  the  conjunctiva, 
generally  found  between  the  limbus  of  the  cornea  and 


126  LESSONS    ON    THE    EYE. 

the  plica  semilunaris,  but  sometimes  on  the  temporal 
side.  It  is  composed  of  connective  tissue  and  elastic 
fibers.  It  is  of  frequent  occurrence,  does  no  harm  and 
need  not  be  removed. 

SYMBLEPHARON. 

This  is  a  cicatricial  adhesion  between  the  conjunctiva 
of  the  lid  and  the  conjunctiva  of  the  ball  and  is  the 
result  of  the  apposition  of  two  raw  surfaces,  which  may 


Symblepharon. 


have  been  produced  by  operations,  ulcers,  burns,  etc. 
The  treatment  is  operative  and  difficult.  After  dissect- 
ing the  lid  from  the  ball  the  raw  surfaces  must  be 
thoroughly  covered  by  mucous  membrane  or  they  will 
promptly  reunite. 


Burns  of  the  conjunctiva  are  serious  because  they 
lead  to  the  adhesion  between  the  hds  and  globe  just 
described. 

Powder  burns  may  only  involve  the  outside  of  the 
lids  and  may,  if  the  eye  is  not  closed  quickly  enough, 
seriou.sly  damage  the  cornea  and  entail  loss  of  sight. 


DISEASES    OF    THE    CONJUNCTIVA.  1 27 

The  burns  of  percussion  caps  and  torpedoes  are  espe- 
cially destructive,  owing  to  the  added  evil  of  the  chem- 
ical action  of  the  fulminate  of  silver  and  mercury  of 
which  they  are  made.  All  the  foreign  particles  should 
be  carefully  picked  out  of  the  skin  and  cornea,  an  ano- 
dyne given  to  control  the  pain,  and  the  eye  put  u])  in 
an  aseptic  castor  oil  dressing.  If  the  cornea  is  much 
injured  atropin  should  be  used,  as  there  is  danger  of 
secondary  iritis. 

Beard  suggests  antiseptic  and  anodyne  treatment 
for  two  or  three  days,  then  the  use  of  H.O,.  The 
tissue  around  the  foreign  bodies  has  by  this  time 
become  softened  and  the  gas  generated  by  the  per- 
oxid  lifts  out  the  particles  of  powder. 

Lime  burns  must  be  w^ashed  copiously  with  tepid 
water  and  all  particles  picked  out  with  forceps  if  an 
anesthetic  has  to  be  given  to  accomplish  it.  An 
anodyne  can  be  given  and  holocain  used  locally. 
Adhesions  should  be  broken  every  day  and  sweet  oil 
or  castor  oil  dropped  between  the  lids.  If  the  l)urn  is 
deep  symblepharon  will  follow. 

It  has  been  found  by  zur  Nedden  that  the  corneal 
opacity  soon  changes  to  carbonate  of  lime  and  when 
this  takes  place  Httle  can  be  done.  He  recommends 
the  immediate  free  application  three  times  a  day  of  a 
5  or  10  per  cent,  solution  of  ammonium  tartrate  neu- 
tralized by  the  addition  of  liquor  ammonia?. 

Acid  burns  should  be  thoroughly  cleansed  with  weak 
bicarbonate  of  soda  solution,  and  the  raw  surfaces, 
pain  and  inflammation  combated  as  in  the  case  of  lime 
burns.  Atropin  should  always  be  used  where  there 
is  danger  of  iritis. 


128 


LESSONS    ON    THE    EYE 


SUB-CON JUNCTIVAL    ECCHYMOSIS. 

A  hemorrhage  under  the  conjunctiva  may  be  due  to 
a  strain,  traumatism  or  disease  of  the  blood  vessels. 
It  is  seen  often  in  children  with  whooping  cough,  and 
need  cause  no  uneasiness.  Coming  on  in  an  adult, 
without  strain  or  accident,  it  indicates  weakness  of 
the  vessel  walls  and  portends  hemorrhages  in  other 
organs,  which  might  be  of  serious  consequence.  There 
is  no  pain  attending  the  condition  and  treatment  is 
unnecessary.  Hot  applications  may  hasten  absorption 
of  the  clot. 

MORBID    GROWTHS    IN    THE    CONJUNCTIVA. 

The  abnormal  growths  which  may  develop  in  the 
conjunctiva  will  only  be  mentioned.  The  diagnosis  and 
treatment  of  these  conditions  lie  along  surgical  lines. 


Thickeninji  of  the  lower  lid  flue  to  a  mass  of  tul)crcular  ncdules. 


The  conjunctiva  may  be  the  vSite  of  a  j)nmar)-  syph- 
ilitic sore,  or  a  secondary  mucous  patch  and  a  ter- 
tiary gumma  of  the  conjunctiva  has  been  reported. 
Tf    a    true    chancre    is    jircstMit     the    ])reaiincu]ar   and 


DISEASKS    ()|-     rilK    CONJUNCTIVA.  129 

submaxillary    ^^lands    will    be    swollen.      Treat mcnt    is 
constitutional. 

Tuberculosis  of  the  conjuncti\-a,  though  a  rare 
disease,  is  now  being  more  often  recognized.  It  may 
appear  in  a  number  of  forms  but  most  frequently  occurs 
as  an  ulcer.  The  next  most  frequent  variety  is  that 
characterized  by  yellowish  subconjunctival  nodules 
which  may  be  mistaken  for  trachoma  folHcles.  The 
detection  of  conjunctival  tuberculosis  often  requires 
fine  diagnostic  discrimination.  EpitheHomata  and 
sarcomata  may  develop,  and  usually  elect  the  limbus 
as  their  starting-point.  Thorough  removal  is  im- 
perative. Some  cases  demand  sacrifice  of  the  eyeball 
and  orbital  contents,  but  even  this  does  not  always 
save  the  patient.  Lipomata  are  found  under  the 
conjunctiva,  between  the  superior  and  external  rectus 
muscles  and  must  be  differentiated  from  a  dislocated 
lacrymal  gland.  Papillomata  may  grow  from  any 
part  of  the  conjunctiva,  while  dermoid  tumors  are,  as 
a  rule,  found  as  congenital  formations,  near  the  outer 
canthus.  Cysts,  nevi  and  angiomata  are  also  found 
in  the  conjunctiva. 


LESSON  XVII. 

DISEASES  OF  THE  CORNEA. 

PHLYCTENULAR    KERATITIS. 

Phlyctenular  keratitis  and  phlyctenular  conjunc- 
tivitis are  the  same  disease,  the  only  difference  being 
in  the  location  of  the  vesicle.  The  small  nodule,  which 
is  the  characteristic  feature  of  the  disease,  may  be 
located  on  the  scleral  conjunctiva  or  on  the  cornea, 
but  is  most  frequently  found  between  the  two,  at  the 
limbus.  When  on  the  cornea,  all  the  symptoms  are 
more  severe  than  when  the  disease  is  conjunctival,  and 


Fig.  86. — Phlyctenular  conjunctivitis,      (.\fler  Dalrymple.) 

it  is  only  when  corneal  that  it  can  leave  any  changes 
which  impair  vision.  The  numt»er  of  vesicles  is  not 
limited,  and  it  is  possible  to  ha\-e  them  on  the  cornea 
and  conjunctiva  at  the  same  time. 

Symptoms. — The   so-called    vesicle,   a  small  nodule 
(red  if  on  the  conjunctiva,  gray  if  on  the  cornea),  is  at 
first    a    circumscribed    accumulation    of    leucocytes, 
130 


DISEASES    OF    THE    CORNEA.  J  _:;  J 

under  the  epithelial  layer,  l)iit  soon  develops  into  an 
uleer.  The  conjunctiva  is  injected,  and  there  is  a 
tendency  of  the  enlarged  vessels  toward  the  phlyctenule. 
Photophobia  and  pain  are  severe,  which  produces 
strong  blepharospasm.  The  child  will  keep  its  face 
in  the  dark  and  any  effort  to  bring  it  to  the  light,  for 
the  purpose  of  examination,  will  meet  with  strong 
resistance.      Lacrymation     is    pronounced.      Marginal 


KlG.  87. — Phlyctenular  keratitis,  (.\fter  IwanotT.)  This  consists  of  a 
collection  of  pus  cells  between  the  epithelium  and  the  substantia  projiria. 
The  band  passing  obliquely  to  it  is  a  corneal  nerve. 

blepharitis  is  often  present.  Generall}'  there  is  a 
discharge  from  the  nose,  and  eczematous  scabs  form 
around  the  lips  and  nostrils.  There  may  be  enlarge- 
ment of  the  lymphatic  glands  and  other  evidences  of  a 
strumous  diathesis.  Usually  the  disease  recovers  in 
a  few  weeks,  leaving  no  permanent  injury,  but  relapses 
are  the  rule.  Faint  opacities  of  the  cornea  may  be  left, 
which,  if  over  the  pupil,  will  impair  vision.  In  rare 
instances  deep  ulceration  of  the  cornea  may  develop, 
followed  by  secondary  iritis,  perforation  or  staphyloma. 
Cause. — It  is  a  disease  of  childhood,  and  is  supposed 
to  be  due  to  some  irregularity  of  nutrition,  the  result 
of  the  strumous  diathesis.     Leitner  found  scrofulosis 


132  LKSSONS    ON    THE    EYK. 

present  in  88.7  per  cent,  of  the  585  children  with 
phlyctenular  conjuncti\'itis  examined  by  him.  Bad 
hygienic  surroundings  and  insufficient  nourishment 
seem  to  contribute  to  the  disease,  and  yet  it  is  frequently 
seen  in  otherwise  healthy  children. 

Treatment. — The  cause  being  constitutional,  give 
fresh  air,  wholesome  food,  tonics  of  syrup  of  the  iodid 
of  iron,  malt  or  cod  liver  oil,  and  keep  bow^els  regular. 
Small  doses  of  calomel  are  efficacious.     Dusting  the 


Fig.  88. — Phlyctenular  ulcer. 

cornea  with  finely  powdered  calomel,  once  a  day.  is 
recommended  but  must  not  be  done  if  the  patient  is 
taking  potassium  iodid.  Promote  health  in  every  way. 
Tubercular  subjects  should  receive  treatment  ap- 
propriate to  this  disease.  Use  locally  hot  fomentations 
and  a  weak  ointment  of  yellow  oxid  of  mercury  rubbed 
in  gently  once  a  day.  Atropin  is  often  indicated.  If 
pronounced  corneal  ulceration  develops,  follow  the 
treatment  for  such  a  condition  (page  140).  Consti- 
tutional treatment  should  be  continued  after  the  dis- 
appearance of  the  local  disease. 

INTERSTITIAL    KERATITIS. 

This  is  a  disease  of  childhood  but  may  ])e  found  in 
adult    life.      Both   eves   arc   usualK'    in\ol\-c(l,    one   in 


DISEASES    OF    THE    CORXEA.  133 

ach'ance  of  the  other.  The  suhstaiUia  ])ro])ria  is  the 
part  primarily  involved  The  deep  layers  soon  par- 
ticipate in  the  inflammation,  and  in  severe  cases  the 
uveal  tract  rarely  escapes.  The  course  of  the  disease 
is  chronic,  sometimes  extending  over  two  or  three  years. 
Relapses  are  common.  The  prognosis  is  favorable, 
although  only  a  few  cases  escape  without  some  im- 
pairment of  \'ision.  In  a  limited  number  sight  is 
permanently  lost. 


Fig.  89. — Interstitial  keratitis.     (Nettleship.) 

Symptoms. — At  first  the  eye  will  indicate  a  state  of 
irritability.  There  will  be  some  photophobia,  lacry- 
mation  and  circumcorneal  h}'peremia.  Vision  will 
become  blurred  and  inspection  will  reveal  an  infiltra- 
tion of  the  deeper  layers  of  the  cornea,  which  gives  it 
an  opaque  or  hazy  appearance.  This  haziness  may 
begin  in  the  center  or  it  may  start  from  the  scleral 
margin.  Small  blood  vessels  will  be  seen  springing 
from  the  corneal  periphery  and  extending  toward  its 
center.  These  blood  vessels  are  deep  in  the  substantia 
propria  and  if  numerous  will  give  the  inflamed  area 
a  salmon  pink  color.  The  opacity  of  the  cornea  may 
become  complete  in  a  short  time  and  vision  be  reduced 
to  light  perception.  Iritis  may  occur,  with  a  tendency 
toward  the  inflammation  extending  to  the  ciliarv  body 


1  U  LESSONS    ON   THE   EYE. 

and  choroid.  When  resolution  sets  in  the  opacity 
begins  to  disappear  at  the  margin,  the  center  of  the 
cornea  being  the  last  part  to  become  transparent. 
When  the  iris  can  be  seen,  posterior  synechiae  may 
be  found  and  when  the  fundus  can  be  examined  we  may 
find  evidences  of  choroidal  inflammation.  Associated 
with   the  eye  symptoms  we  generally   find   e\-idences 


jmm^ 


^ 


Fig.  90. — Hutchinson's  teeth.     .^Iso  the  syphilitic  scars  at  the  angles  of  the 
mouth. 

of  inherited  syphilis;  glandular  enlargement,  sunken 
nose,  ozena,  Hutchinson's  teeth,  scars  at  the  angles  of 
the  mouth,  the  vaulted  palate  and  the  -characteristic 
physiognomy. 

Cause. — Nettleship  claims  to  have  found  evidences 
of  inherited  syphilis  in  68  per  cent,  of  his  cases,  and 
suspects  it  in  the  remaining  32  per  cent.  However 
acquired,  syphilis,  tuberculosis  and  traumatism  were 
the  undoubted  causes  of  numerous  cases  reported. 
It  is  said  also  to  be  caused  by  scrofula  and  rheumatism. 

Tr€at]}ient. — Use  smoked  glasses  to  protect  the  eyes 


DISEASES    (JF    TllK    CORNEA.  I35 

from  the  light.  Apply  hot  appHcatioiis  lor  thirty 
minutes  at  a  time  three  or  four  times  a  day.  Drop 
into  eyes,  twice  a  day,  a  i  ])cr  cent,  solution  of  sulfate 
of  atropin.  Use  atropin  more  frequently  if  necessary 
to  keep  the  pupil  dilated.  Unless  the  symptoms  point 
conclusively  to  some  other  cause  assume  the  existence 
of  syphilis  and  give  anti-syphilitic  remedies  with  tonics, 
good  food  and  good  air.  After  the  acute  symptoms 
have  subsided  use  a  w^eak  ointment  of  the  yellow  oxid 
of  mercury  (grs.  2  to  o^)  putting  into  the  conjunctival 
sac,  once  a  day,  a  quantity  al:)out  half  the  size  of  a  pea. 
The  ointment  can  be  thoroughly  disseminated,  and 
at  the  same  time  a  massage  of  the  cornea  effected,  by 
placing  a  finger  on  the  closed  lid  and  giving  it  a  gentle 
lateral  or  rotary  movement.  Dusting  the  cornea  with 
calomel  has  been  recommended,  but  it  must  be  remem- 
bered that  calomel  should  never  be  put  into  an  eye 
when  the  patient  is  taking  iodid  of  potassium,  as  the 
iodid  is  found  in  the  tears  and  with  the  calomel  makes 
an  intensely  irritating  compound,  mercuric  iodid.  If 
the  massage  with  the  yellow  oxid  of  mercury  ointment 
or  the  dusting  with  calomel  causes  undue  reaction,  it 
indicates  that  the  remedy  has  been  employed  too  soon 
and  its  use  should  be  postponed  until  the  eyes  are  less 
sensitive.  Cases  which  are  tubercular  in  origin  may 
be  improved  by  injections  of  tuberculin.  When  the 
acute  symptoms  have  subsided  dionin  may  be  used  to 
promote  the  absorption  of  the  deposits  which  cloud 
the  cornea. 


LESSON  XVIII. 

DISEASES  OF  THE  CORNEA  (Continued) 

ULCERATION    OF    THE    CORNEA. 

Symptoms. — Congestion,  pain,  lacrymation,  impair- 
ment of  vision  and  swelling  of  the  lids  are  associated 
with  ulceration  of  the  cornea,  but  the  latter,  being  due 
to  such  a  diversity  of  causes,  will  show  a  great  variety  of 
symptomatic    pictures.     For    exam])le,    an    eve    with 


Fig.  ()j. — A.  large  superficial  ulcer  of  the  cornea.     The  ulcer  is  surrounded 
by  a  zone  of  infiltration. 

ulceration  of  the  cornea  resulting  from  diphtheritic 
conjunctivitis  will  necessarily  present  a  \'ery  different 
appearance  from  one  in  which  the  ulcer  is  due  to  an 
infected  foreign  body.  Corneal  ulcers  have  also  been 
accurately  classified  according  to  shape,  method  of 
development  and  cause,  but  for  the  purposes  of  the 
student  a  general  description  is  deemed  sufficient. 
136 


DISEASES    OF    THK    CORNF.A.  1^7 

The  part  of  the  eornea  inx'oh'ed  beeomes  infiltrated 
and  appears  hazy,  white  or  yeUow.  This  is  quickly 
followed  by  a  loss  of  corneal  substance.  The  destruc- 
tion of  tissue  may  spread  superficially  or  may  involve  the 
deeper  layers  and  result  in  speedy  perforation.  The 
ulcer  wnll  be  surrounded  by  a  hazy  zone  of  infiltrated 
tissue,  the  region  of  densest  infiltration  correspond- 
ing to  the  directicMi  in  which  the  ulcer  is  most  liable  to 
progress.  If  the  disintegrating  y)rocess  only  in\-olves 
the  first  two  lavers,  re])air  \\'ith  trans])arent  tissue  will 


Fig.  92. — Beginning  corneal  ulcer.  (After  Sacmisch.)  The  upper  layers 
of  epithelium  are  partly  lacking.  .\t  Bowman's  membrane  a  layer  of  pus- 
cells  is  seen.  In  the  substantia  ])roj)ria  are  numerous  small  grou])s  of  [lus- 
cells. 


result,  but  any  loss  of  the  deeper  layers  will  usually  be 
replaced  by  an  opaque  scar.  An  ulcer  will  meet  with 
greater  resistance  from  the  membrane  of  Descemet 
than  from  any  other  layer  of  the  cornea,  and  is  often 
checked  at  this  point.  If  Descemet's  membrane  gives 
way,  perforation  follows.  When  this  takes  place  the 
aqueous  escapes  and  the  iris  and  lens  come  forward  to 
the  cornea.  If  the  iris  adheres  permanently  to  the 
corneal  cicatrix,  we  have  a  condition  called  anterior 
synechia.  Contact  of  the  anterior  lens  capsule  with 
the  cornea  is  liable  to  produce  an  opacity  of  the  capsule 


138 


LESSONS    ON    THE    EYE. 


at  the  point  of  contact  if  the  i)atient  be  \ery  young. 
When  the  aqueous  escapes  the  tension  is  reheved  and 
the  lymph  circulation  in  the  cornea  becomes  freer, 
which  accounts  for  the  improvement  so  often  noted  after 
perforation.  Iritis  occurs  frequently  and  is  sure  to 
occur  if  the  deeper  layers  of  the  cornea  are  involved. 
Adhesion  of  the  iris  to  the  lens  capsule  or  posterior 
synechia  must  be  guarded  against.  The  cihary  body 
mav  become  involved.    In  some  cases  there  is  an  exuda- 


FiG.  93. — Ulcer  of  the  cornea.  The  epitheHuni^  Bowman's  membrane 
and  part  of  the  substantia  propria  are  gone.  The  floor  of  the  ulcer  is  infil- 
trated with  pus-cells. 

tion  of  non-pathogenic  pus  from  the  iris  which  forms 
at  the  bottom  of  the  anterior  chamber.  Pus  in  the 
anterior  chamber  is  called  hypopyon.  The  presence  of 
hypopyon  adds  gravity  to  the  disease,  and  in  such  cases 
the  prognosis  should  be  extremely  guarded.  The 
entire  cornea  may  melt  away  and  the  eyeball  still  be 
preserved  by  the  formation  of  a  white,  fibrous  cicatrix 
where  the  cornea  was.  This  new  tissue  may  not  be  as 
resisting  as  the  cornea,  and  is  liable  to  be  protruded  by 
the   intra-ocular   pressure,    causing   staphyhmui    (page 


DISEASES    OF    THE    CORNEA.  1 39 

145).  After  perforation  intra-oeular  infeetion  may 
occur  and  the  eye  be  destroyed  1)\-  pauophthaliuitis 
(page  171). 

Cause. — The  exciting  cause  is  a  pathogenic  microbe, 
generally  the  white  or  yellow  staphylococci,  the  pneu- 
mococcus,  the  streptococcus,  the  diplobacillus,  the 
gonococcus.  the  xerosis  bacillus,  the  aspergillus  fumi- 
gatus  or  the  bacillus  pyocyaneous.  The  source  of 
the    germ    ma>-    be    purulent    conjunctivitis,    dacryo 


.(   -  :--^^ 


Fig.  g4. — The  cornea  after  ulceration,  showing  the  scar  tissue. 

cystitis,  erysipelas,  diphtheria,  ozena,  septic  fingers, 
handkerchiefs  and  instruments,  or  an  unknown  source. 
The  predisposing  cause  is  some  condition  which 
renders  the  cornea  more  susceptible  to  infection.  This 
mav  be  a  debilitating  disease,  an  injur}^  from  a  foreign 
bodv,  an  operation,  lagophthalmia  (paralysis  of  the 
seventh  nerve),  or  paralysis  of  the  fifth  nerve.  The 
ulceration  due  to  paralysis  of  the  fifth  is  called  neuro- 
paralytic keratitis.  With  paralysis  of  the  fifth  there  is 
loss  of  sensation,  foreign  bodies  are  no  longer  removed 


140  LESSONS    ON    THE    EYE. 

from  the  cornea,  Vjy  the  reflex  action  of  the  lids,  and 
abrasion  results.  Abrasion  is  further  facilitated  by 
the  dryness  of  the  cornea  which  exists  in  the  absence 
of  winking. 

Treatment. — When  the  ulcer  is  due  to  purulent  con- 
junctivitis, dacryocystitis,  erysipelas,  diphtheria,  etc.. 
the  primary  disease  must  be  treated  vigorously.  Mi- 
croscopic examination  of  the  necrotic  tissue  should  be 
made  in  order  to  identify  the  responsible  germ.  If  the 
secretion  is  scant  the  lids  should  be  immobilized,  V)e- 


FiG.  95. — Perforating  ulcer  of  the  cornea,  adhesion  of  iris  (anterior  synechia). 

tween  treatments,  by  a  light  bandage,  if  abundant  the 
bandage  should  not  be  used.  In  some  cases  it  is  best 
to  keep  the  eye  hermetically  sealed  between  the  daily 
antiseptic  dressings.  The  focus  of  germs  should  be 
destroyed  by  touching  the  ulcer  with  a  galvanic  cauterv, 
tincture  of  iodin,  carbolic  acid,  20  per  cent,  trichlor- 
acetic acid,  I  to  100  formal,  or  by  scraping  it  clean  with 
a  small  curette.  This  should  be  done  under  holocain 
(i  per  cent.)  anesthesia.  Holocain  is  preferable  to 
cocain  as  it  does  not  dry  the  corneal  epithelium,  and 
also  possesses  some  antiseptic  properties.  The  con- 
junctival sac  should  be  cleansed  out  about  three  times 
a  day  with  bichlorid  or  cyanid  of  mercury  solution" 
I  to  8,000.     The  cleansing  may  be  repeated  more  fre- 


DISKASKS    OK    THK    CORNKA.  I4I 

(lucnlh-  if  a  saturated  solution  of  l)()racic  acid  or  bihoratc 
of  soda  is  used.  The  direct  applicaticMi  of  a  stron^^ 
protargot  solution  (20  per  cent.)  has  been  extolled. 
Argyrol  (10  to  40  i)er  cent.)  may  be  used.  Zinc  in 
some  form  should  be  freely  applied  if  the  ulcer  is  due 
to  the  diplobacillus  of  Morax  and  Axenfeld.  Dionin 
is  said  to  stimulate  corneal  regeneration.  Covering  the 
ulcer  with  finely  powdered  nosophen  or  xeroform  is 
advised.  Hot  fomentations  should  be  applied  for 
thirtv   minutes   at   a   time   everv   four  hours.     Abcnit 


Fig.  96. — Hypopyon,  seen  from  the  front,  and  in  section,  to  sliow  that  the 
pus  is  behind  the  cornea.     (Nettleship.) 

three  times  a  day  instil  a  drop  of  a  i  per  cent,  solution 
of  atropin  to  relieve  iritic  congestion  and  prevent 
posterior  svnechia.  Some  advise  the  use  of  eserin  to 
relieve  intra-ocular  tension  and  thus  improve  the 
lymph  circulation  in  the  cornea,  but  this  is  manifestly 
dangerous  if  the  iris  is  involved.  The  value  of  sub- 
conjunctival injections  and  the  serum  treatment  is  still 
undetermined.  Paracentesis  will  relieve  the  tension, 
and  is  sometimes  indicated,  especially  if  perforation  is 
imminent.  The  patient  should  be  kept  quiet  and  the 
constitution  sustained  by  iron,  quinin,  and  strychnin 
tonics.  The  internal  administration  of  large  and  fre- 
quent doses  of  dilute  sulfuric  accd  seems  to  create  a 


142  LESSONS    ON    TllK    EVE. 

conditicjii  in  the  tissues  antagonistie  tu  ])us  formation. 
It  has,  at  times,  appeared  to  check  the  ulcerative 
process  in  the  cornea.  If  the  ulceration  is  neuropara- 
lytic or  is  due  to  paralysis  of  the  seventh  nerve,  the 
cornea  must  be  protected  by  the  lid  and  a  bandage 
or  adhesive  plaster  will  be  necessary  to  accomplish  it. 


LESSON  XIX. 

DISEASES  OF  THE  CORNEA  (Cond)  AND  SCLERA. 

VASCULAR  KERATITIS  OR  PANNUS. 

The  upper  half  of  the  cornea  is  the  part  most  frequently 
affected,  but  its  whole  surface  may  be  involved.  It 
becomes  grayish  in  color  from  cellular  infiltration  and 
covered  by  a  mesh  of  fine  blood  vessels,  which  grow 
from  the  conjunctiva.  The  infiltration  and  vascularity 
are  found  between  the  epithelial  and  Bowman's  layers, 


ii^'^^^ 


"mm 

Fig.   i)-j.     I'annus.      (Kick.) 

but  may  go  deeper.  If  the  new  growth  inxades  the 
substantia  propria  permanent  scarring  is  the  result. 
Vision  is  impaired  and  may  be  reduced  to  hght  percep- 
tion. As  pannus  is  secondary  to  some  other  ocular 
disease,  the  general  symptoms  will  be  those  of  the  pri- 
mary affection. 

Cause. — Pannus  is  most  frequently  caused  ])y  tra- 
choma, pannus  trachomatosus.  Repeated  attacks  of 
phlyctenular  keratitis  may  result  in  pannus  scrofulosa. 

143 


144  LESSONS    ON     IHK    KYF.. 

Ingrowing  lashes,  irritciticjn  of  the  eornea  from  imper- 
fect closure  of  the  lids,  etc.,  produce  traumatic  pannus. 
Treatment. — Attend  to  the  primary  disease.  The  use 
of  an  infusion  of  jequirity  produces  a  severe  purulent 
inflammation,  which  often  results  in  great  improve- 
ment and  sometimes  cure  of  the  pannus,  but  this  treat- 
ment should  be  left  to  an  oculist.  Fox  recommends  the 
operation  of  peridectomy,  which  consists  in  excising  a 
strip  of  bulbar  conjunctiva  2  to  5  mm.  wide  immedi- 
ately surrounding  the  cornea. 

OPACITIES  OF  THE   CORNEA. 

Nebula,  macula,  and  leucoma  are  names  given  to 
different  degrees  of  opacity  of  the  cornea.  These  opaci- 
ties usually  represent  scar  tissue,  which  has  replaced 
the  loss  of  substance  occasioned  by  an  ulcer,  but  they 
may  be  due  to  an  infiltration  or  a  traumatism.  If  the 
first  two  layers  of  the  cornea  are  destroyed  they  may 
heal  without  leaving  any  sign,  but  any  loss  of  the  deeper 
layers  is  generally  repaired  with  scar  tissue.  The 
amount  of  damage  to  sight  produced  by  an  opacity 
depends  upon  its  location  relative  to  the  pupil.  Recent 
scars  are  improved  by  time  and  direct  massage  with  a 
stimulating  ointment,  but  old  ones  will  remain  un- 
changed. The  persistent  use  of  dionin  has  been  bene- 
ficial. If  the  opacity  is  central  and  there  is  any  per- 
ipheral clear  cornea,  an  artificial  pupil  may  improve 
vision.  Before  advising  an  iridectomy  it  is  wise  to 
dilate  the  pupil  to  the  maximum  extent  and  observe  if 
this  measure  improves  vision ;  if  not,  a  false  pupil  will 
be  of  little  service.     At  times  vision  is  much  impaired 


DISEASES    OF    THE    CORNEA. 


145 


by  opacities  which  are  so  faint  that  they  may  be 
overlooked  by  inspection,  even  with  obhque  illumina- 
tion. With  an  ophthalmoscope  and  transmitted  light 
they  will  be  seen.  The  exact  locality  of  such  an  opac- 
ity, whether  in  the  cornea,  anterior  or  posterior  part  of 
the  lens,  is  often  not  easy  to  determine  (Fig.  98). 


Fig.  98. — Localization  of  opacities  in  cornea  and  lens. 


STAPHYLOMA. 

Severe  ulceration  of  the  cornea  so  decreases  its  power 
of  resistance  that  the  normal  intra-ocular  pressure  may 
cause  it  to  bulge  forward,  destroying  the  natural  curve. 
The  distention  may  involve  the  whole  cornea  or  only 
part  of  it.  When  staphyloma  is  the  result  of  a  perfo- 
rating ulcer,  the  iris  may  be  caught  in  its  tissue.  This 
anterior  synechia  may  cause  recurring  attacks  of  iritis 
and  even  deeper  intra-ocular  inflammation.  The 
staphylomatous  cornea  is  never  transparent.     It  mav 


146 


LESSONS    ON    THE    EYE. 


be  stationary  or  progressive.  It  may  be  small  or  so 
large  that  the  lids  will  not  close  over  it.  In  some  cases 
nothing  need  be  done.     The  treatment  is  operative. 


Fig.  99. — Total  staphyloma.     (Pick.) 


ARCUS  SENILIS. 


A  narrow  white  ring  is  often  seen  near  the  circumfer- 
ence of  the  cornea.  It  is  usually  found  in  old  people, 
Init  may  occur  in  the  young.     It  is  caused  by  hyaline 


Fig. 


-.\n  arcus  senilis. 


degeneration  and  requires  no  treatment.  It  has  no 
influence  on  the  healing  of  wounds,  as  for  examjile  the 
incision  in  cataract  operation. 


DISEASKS    OF    THE    CORNEA. 


147 


CONICAL  CORNEA,   OR  KERATOCONUS. 

Sometimes  the  centerof  the  cornea  becomes  weakened 
by  an  atrophic  ]jrocess  and  the  intra-ocular  pressure 
pushes  it  forward  ;  the  convex  sphere  changing  to  a  cone. 
The  cornea  remains  clear  except  for  the  occasional 
appearance  of  a  nebula  at  its  apex.  The  process  is  slow 
and  gradual  but  finallr  reaches  a  point  w^here  it  stops. 


Kenitoa 


(Afu 


Vision  is  greatly  impaired.  Inspection  of  the  eye 
reveals  no  abnormality,  except  in  pronounced  cases, 
when  a  side  view  will  show  its  conical  form.  Diagnosis 
in  the  early  stages  is  difficult  and  treatment  not  very 
effective.     The  latter  should  be  left  to  an  oculist. 


FOREIGN    BODIES    IN    THE    CORNEA. 

It  is  very  common  for  cinders,  sand,  pieces  of  emory, 
iron,  steel,  etc.,  to  become  lodged  in  the  cornea.  Pain 
and  lacrvmation  will  be  intense,  with  more  or  less  cir- 


148 


LESSONS    ON    THE    EYE. 


cumcorneal  injection.  If  simple  inspection  does  not 
reveal  the  offender,  use  oblique  illumination.  This  is 
done  by  seating  the  patient  about  two  feet  from  a  light 
and  with  a  i6  or  20  diopter  convex  lens,  focus  the  rays 


Fig.  102. — Spud  for  remc 


f<)reic;n  bodies. 


obliquely  on  the  part  to  be  examined.  Then  by  viewing 
the  illuminated  area  through  a  magnifier,  the  cornea, 
iris,  and  anterior  part  of  the  lens  may  be  thoroughly 
inspected.     One  of  the  binocular  magnifiers  is  indispen- 


FiG.  loj. — ObliquL'  illumination. 

sable  in  such  work.  To  remove  a  foreign  body,  the 
cornea  should  first  be  anesthetized  by  several  drops  of 
a  4  per  cent,  solution  of  cocain  or  a  1  ])er  cent,  solu- 
tion of  holocain;  ihcn,  with  a  needle  or  s])U(l  ])ick  it  out 


niSKASKS    Ol'    THK    SCLKKA.  M*) 

with  as  liUk'  destruction  to  corneal  tissue  as  possible. 
When  the  epithelium  is  denuded  there  is  always  danger 
of  infection;  therefore,  an  antiseptic  collyrium  (solution 
hydrarg.  bichlorid  i  t(^  8,000)  should  be  used  for  three  or 
four  days,  or  until  the  epithelial  layer  is  restored. 
Another  way  to  prevent  infection  of  the  cornea  when 
the  epithelium  has  been  denuded,  is  to  touch  the  lesion 
lightly  with  compound  tincture  of  benzoin.  A  thin, 
adherent  ])ellicle  is  immediately  formed,  which  covers 
the  wound  for  from  six  to  twelve  hours.  Probably  the 
safest  way  to  pre\-ent  infection  is  to  clean  the  eye 
antise]^tically  and   seal  it  up  between  daily  dressings. 

DISEASES  OF  THE  SCLERA. 

EPISCLERITIS. 

Under  the  ocular  conjunctiva  is  a  delicate  membrane, 
the  capsule  of  Tenon,  and  between  the  capsule  of  Tenon 
and  the  sclera  proper  is  the  loose  connective  tissue 
called  the  episclera.  These  parts  are  so  intimately 
related  that  inflammation  of  the  subconjunctival  tissues 
generally  involves  the  overlying  conjunctiva  and  may 
go  deeper  into  the  sclera  proper.  Scleral  and  episcleral 
inflammation  is  limited  to  the  region  anterior  to  the 
equator. 

Symptoms. — In  episcleritis  there  appears  a  patch  of 
dusky  red  injection  under  the  conjunctiva,  generally 
between  the  insertion  of  a  rectus  muscle  and  the  cornea. 
There  may  be  a  distinct  nodule  which  will  tend  to  con- 
found the  disease  with  phlyctenular  conjunctivitis.  The 
age  of  the  patient  and  the  fact  that  the  episcleral  nodule 
does  not  ulcerate  will  aid  in  the  differentiation.     The 


150  LESSONS    ON    THE    EYE. 

discliars^a'  from  the  eye  is  watery  and  pain  and  i)hoto- 
pholjia  arc  generally  slight.  The  inflamed  spot  may 
disappear  spontaneously,  may  persist  for  weeks,  has  a 
tendency  to  recur,  and  will  often  leave  a  gray,  discolored 
patch. 

Cause. — Rheumatism,  gout,  tuberculosis,  syphilis,  and 
menstrual  derangement.  It  may  arise  from  exposure 
to  the  weather  and  is  also  said  to  appear  over  the  inser- 
tion of  a  rectus  muscle  suffering  from  insufficiency. 
Frequentl}*  the  cause  is  obscure. 

Treatment. — Some  cases  are  so  mild  as  to  need  no 
treatment.  The  constitutional  cause,  if  discoverable, 
should  be  attended  to.  Correct  muscular  anomalies 
and  refractive  errors.  Apply  hot  fomentation.  Use 
atropin,  if  there  is  any  tendency  toward  iritis.  When 
chronic,  stimulation  with  yellow  oxid  of  mercurv  oint- 
ment is  useful. 

SCLERITIS. 

Inflammation  of  the  sclera  may  be  circumscribed  or 
diffuse.  It  resembles  episcleritis,  but  the  symptoms  are 
all  more  severe  and,  as  a  deeper  structure  is  inflamed, 
there  is  much  greater  danger  of  involvement  of  the  uvea. 
The  discharge  is  watery  and  pain  and  photophobia  may 
be  pronounced.  The  inflammation  may  extend  to  the 
underlying  uveal  tract  and  produce  iritis,  cyclitis,  or 
choroiditis ;  or  extend  to  the  cornea,  producing  a  haziness 
of  its  deep  layers  (sclero-keratitis) .  These  complica- 
tions may  lead  to  an  impairment  or  total  loss  of  vision. 
Tension  is  often  increased.  The  condition  is  chronic  in 
its  course,  sometimes  extending  over  a  period  of  years. 
The  scleral  wall  may  become  so  thinned  that  the  dark 


DISEASES    OF    THE    SCLERA.  I5I 

uvea  showing  throui^h  il  will  <^\yc  it  a  puri)lish  hue. 
The  imperfect  resistance  of  the  thinned  sclera  will 
result  in  bulging  or  staphyloma  of  its  weakest  parts. 

Cause. — The  cause  is  generally  rheumatism,   gout, 
syphilis,   tuberculosis,  or  menstrual  disorders. 


Fig.  104. — Staphyloma  of  the  sclera. 

Treatment. — For  the  syphilitic  form  use  mercury  and 
iodid  of  potassium.  In  scrofulous  cases,  tonics,  good 
air,  and  good  food.  When  due  to  rheumatism,  salicy- 
late of  sodium,  Rochelle  salts,  etc.  If  gouty  in  origin, 
iodid  of  potassium  or  colchicum.  Combine  above 
treatment  with  hot  baths,  warm  fomentations  over 
eyes,  leeching  of  the  temples,  and  atropin  locally.  The 
increased  tension  and  staphyloma  may  be  improved 
by  a  wide  iridectomy. 


LESSON  XX. 

DISEASES  OF  THE  IRIS. 

Mydriasis  or  dilatation  of  the  pupil  may  be  due  to 
many  causes,  among  which  are: 

1 .  The  use  of  drugs  called  mydriatics,  such  as  atropin, 
homatropin,  scopolamin,  andcocain.  Most  mydriatics 
also  produce  paralysis  of  accommodation. 

2.  Increase  of  intra-ocular  pressure,  as  in  glaucoma. 

3.  Loss  of  vision,  as  in  atrophy  of  the  optic  nerve. 

4.  Paralysis  of  the  third  nerve. 

5.  Dimness  of  light. 

6.  Ingestion  of  certain  drugs,  belladonna,  ergot,  etc. 

7.  Apoplexy  in  the  later  stages. 

Myosis  or  contraction  of  the  pupil  may  be  due  to : 

1.  The  use  of  drugs  called  myotics,  such  as  eserin 
and  pilocarpin.  The  myotics  also  stimulate  accom- 
modation. 

2.  Evacuation   of  the   aqueous  humor. 

3.  Hyperemia  of  the  iris,   as  in  iritis. 

4.  Paralysis  of  the  cervical  sympathetic  nerve. 

5.  Bright  light,  accommodation  and  convergergence. 

6.  Ingestion  of  certain  drugs,  as  opium  and  alcohol. 

7.  Apoplexy  in  the  early  stages. 

The  Argyll-Robertson  pupil  is  one  which  responds 

to  convergence  but  not  to  light,  and  is  significant  of 

locomotor  ataxia.     The   variations   of   mydriasis   and 

myosis  dependent  u]^()n  irritation  and  disease  of  the 

152 


DISEASES    OF    THE    IRIS.  153 

brain  and  spinal  cord  arc  loo  complex  to  dwell  u})on 
here. 

Anterior  synechia  is  an  adhesion  of  the  iris  to  the 
cornea,  due  to  perforation  of  the  cornea  and  lodgment 
of  the  iris  in  the  wound. 

Posterior  synechia  is  an  adhesion  of  the  iris  to  the 
anterior  capsule  of   the  lens.     In   complete  posterior 


Fig.  105. — Posterior  synechia. 

synechia  we  have  what  is  called  exclusion  of  the  pupil. 
Where  the  pupillary  area  is  filled  by  a  membrane,  we 
have  occlusion  of  the  pupil  (Fig.  107). 

IRITIS. 

The  disease  may  be  divided  by  its  course  into  acute 
or  chronic;  pathologically  it  may  be  plastic,  suppura- 
tive or  serous;  etiologically  it  may  be  divided  into  as 
many  forms  as  there  are  causes,  the  leading  varieties 
being  syphiHtic,  rheumatic,  gouty,  tubercular,  and 
traumatic.  The  typical  form  of  iritis  is  plastic;  serous 
iritis,  according  to  Colhns,  Priestley  Smith,  and  others, 
being  more  appropriately  a  cyclitis. 

PLASTIC    IRITIS. 

Symptoms. — Injection  of  the  deep  blood  vessels 
around   the  cornea,   later  extending  over  the  entire 


154  LESSONS    ON    THE    EYE. 

white  of  the  eye.  Diseharge  of  a  watery  eharacter. 
Intolerance  of  Hght  and  pain  of  a  neuralgic  nature, 
beginning  in  the  eyeball  and  extending  over  the  brow, 
temple,  and  cheek.  The  pupil  becomes  small  and  will 
not  react  to  light.  Its  normal  color  changes  to  a 
darker  tone,  a  blue  or  gray  iris  becoming  green.     The 


Fig.    io6. — Congestion  of  iritis.     The  circumcorneal   zone  the  first  part  to 
become  injected.     See  Fig.  74. 


aqueous  becomes  turbid  from  lymphoid  cells,  pus,  and 
red  blood  corpuscles,  and  vision  is  correspondingly  im- 
paired. Adhesion  will  take  place  between  the  iris  and 
anterior  lens  capsule,  constituting  posterior  synechia. 
If  these  adhesions  are  broken,  pigment  deposits  will 
be  left  on  the  capsule  of  the  lens.  When  the  attack 
is  syphilitic  in  origin,  gummata  may  develop   in    the 


DISEASES    OF    TOE    IRIS. 


155 


iris.  If  there  is  iniieli  ]»us  in  the  acjueous  humor 
it  may  settle  in  llie  anterior  elianiher,  ])ro(lneini^- 
hypopyon. 

Sometimes  the  e.xudation  in  the  anterior  ehamber 
leaves  a  membrane  across  the  pupil  which  may  be 
mistaken  for  cataract.  Such  a  condition  is  spoken  of 
as  occlusion  of  the  pupil  (Fig.  107).  Iritis  may  attack 
one  eye  or  both.     Its  duration  depends  largely  upon 


k  r 


Fig.  107. — Exclusion  and  occlusion  of  the  pupil,  with  bulging  of  the  iris 
forward  from  accumulation  of  fluid  in  the  posterior  chamber.  The  posterior 
chamber  (h)  is  thus  made  deeper,  the  anterior  chamber  (v)  shallower,  espe- 
cially where  the  root  of  the  iris  (a)  is  pressed  against  the  cornea.  The  ])Upil 
is  closed  by  an  exudate  membrane  (o).      (Fuchs.) 

the  treatment,  but  will  generally  last  from  two  to  six 
weeks.  In  some  cases  the  eye  will  be  slightly  myopic 
for  weeks  after  an  attack  of  iritis. 

Cause. — In  50  per  cent,  of  all  cases  it  is  due  to 
syphilis,  secondary,  tertiary,  acquired,  or  inherited. 
The  next  most  potent  factors  are  rheumatism,  gout, 
tuberculosis,  and  gonorrhea.  It  may  arise  as  secondary 
to  other  eye  diseases  or  be  due  to  direct  lesions,  acci- 
dental or  operative.  Albuminuria,  diabetes,  mumps, 
disease  of  the  nasal  sinuses,  and  bad  teeth  are  also  said 
to  be  etiological  factors. 


156  LESSONS    ON    THE    EYE. 

'J'rculiiioit.  Prohibit  ^^■ork  and  protect  eyes  with 
shaded  glasses.  Look  to  the  general  health  of  the 
patient,  paying  special  attention  to  the  condition  of  the 
alimentary  canal.  To  prevent  posterior  synechia,  dilate 
the  pupil  with  atropin  and  keep  it  dilated  through  the 
whole  attack.  Leeching  at  the  temple  is  sometimes 
efficacious.  For  the  pain,  give  antipyrin  or  morphin 
and  apply  heat,  dry  or  in  the  form  of  watery  fomenta- 
tion. The  daily  instillation  of  several  drops  of  a  2  per 
cent,  solution  of  dionin  has  a  decided  influence  in  lessen- 
ing the  pain  and  also  seems  to  shorten  the  duration  of 
the  attack.  When  dropped  on  the  eye  it  causes  a  burn- 
ing sensation,  which  can  be  prevented  by  preceding  it 
with  a  drop  or  two  of  cocain.  The  constitutional  treat- 
ment will  depend  upon  the  cause.  In  syphilitic  cases 
give  mercury  and  iodid  of  potassium.  When  rheumatic 
or  gouty  in  origin,  use  the  salicylates,  colchicum,  lithia, 
etc.,  combined  with  hot  baths  or  pilocarpin  sweats. 
Iridectomy  has  been  suggested  for  recurring  iritis,  and 
paracentesis  is  advisable  in  some  cases  with  increased 
tension. 

SUPPURATIVE  IRITIS. 

This  form  is  generally  due  to  wounds  or  operations 
and  does  not  differ  materially  from  the  plastic  form, 
except  that  the  presence  of  pus  infection  makes  the 
symptoms  more  severe  and  the  prognosis  very  grave. 
It  may  also  be  due  to  infectious  diseases,  pyemia,  and 
meningitis. 

SEROUS  IRITIS. 

This  disease  and  serous  cyclitis  are  the  same ;  not  only 
are  the  iris,  ciliary  body,  and  the  choroid  involved,  but 


DiSKASKS  or  Tni;  iris.  157 

also  Descemel's  membrane  of  the  cornea.  It  has  been 
described  under  the  names  descemitis,  keratitis  postica, 
keratitis  punctata,  serous  uveitis,  and  serous  irido- 
cycHtis. 

Symptoms. — Shght  pericorneal  injection,  pain  insify- 
nificant,  vision  sometimes  only  a  little  below  nr)rmal, 
but  maybe  much  lowered,  increase  of  aqueous  evidenced 
by  unusual  depth  of  the  anterior  chamber  and  plus  ten- 


Fig.  108. — Serous  iritis. 


sion.  The  pupil  will  not  be  contracted  as  in  plastic 
iritis  and  the  iris  will  only  be  slightly  discolored.  Pos- 
terior synechia  may  occur,  but  is  not  as  common  as  in 
other  forms  of  iritis.  There  will  also  be  found  a  char- 
acteristic cellular  deposit  in  the  form  of  fine  dots  on  the 
lower  half  of  the  posterior  surface  of  the  cornea,  which 
constitutes  keratitis  punctata.  The  course  of  the  dis- 
ease is  more  or  less  chronic  and  the  subjective  symptoms 
mild  as  compared  with  the  other  forms  of  iritis. 

Cause. — The  causes  are  the  same  as  in  plastic  iritis. 

Treatment. — The  same  as  in  plastic  iritis  except  that 
atropin  must  be  carefully  used,  owing  to  the  danger  of 
increasing  the  tension.  If  the  tension  becomes  danger- 
ous" it  may  be  reduced  by  the  cautious  use  of  pilocarpin 
locally  or  pilocarpin  injections,  to  produce  diaphoresis 
Paracentesis  may  be  necessary. 


LESSON  XXI. 

DISEASES  OF  THE  CILIARY   BODY  AND 
VITREOUS. 

DISEASES  OF  THE  CILIARY  BODY. 

Inflammation  of  the  ciliary  body  is  not  an  isolated 
condition,  but  is  probably  always  associated  with  dis- 
ease of  the  iris  or  choroid.  Cychtis  may  be  acute  or 
chronic;  plastic,  suppurative,  or  serous. 

PLASTIC  AND  SUPPURATIVE  CYCLITIS. 

The  symptoms  of  these  two  conditions  are  the  same 
as  in  iritis,  with  the  addition  of  opacity  of  the  vitreous, 
severe  pain  upon  pressure  over  the  region  of  the  ciliary 
body  and  characteristic  tension,  which  is  plus  in  the 
acute  stage,  but  later  may  become  decidedly  minus,  due 
to  atr()])hy  of  the  ciliary  body  and  shrinkage  of  the  vit- 
reous. The  lens  sometimes  becomes  opaque  and  detach- 
ment of  the  retina  may  occur.  Plastic  cvclitis  is  dan- 
gerous; suppurative  cyclitis  is  almost  always  fatal  to 
vision.     Treatment  is  the  same  as  in  iritis. 

SEROUS  CYCLITIS. 

This  is  the  same  as  serous  iritis  (page  156). 

SYMPATHETIC  OPHTHALMIA. 

Sympathetic  ophthalmia  is  a  diseased  condition  aris- 
ing in  one  eye  caused  by  some  organic  lesion  of  its  fel- 
158 


DISEASES    or    THE    VITREOUS.  1 59 

low.  The  eve  whieh  is  first  alTeeted  is  called  the  exciting 
eye,  while  the  other  is  ealled  the  sympathizing  eye. 

The  disease  takes  two  forms—  sympathetic  irritation 
and  sympathetic  inflammation. 

Symptoms. —  (i)  Sympathetic  irritation  is  a  func- 
tional derangement  characterized  by  intolerance  of 
light,  lacrymation,  and  fatigue  of  the  eye  when  used. 
Visual  acuity  may  be  impaired  and  sometimes  tempo- 
rary obscuration  of  sight  occurs.  There  may  be  con- 
siderable pain,  of  a  neuralgic  character,  in  and  around 
the  eye,  and  also  some  pericorneal  injection.  The  symp- 
toms may  subside,  but  a  relapse  will  occur.  Unless 
the  exciting  eye  is  enucleated,  the  disease  is  prone  to 
develop  into  sympathetic  inflammation. 

(2)  Sympathetic  inflammation  is  sometimes  very 
slow  and  insidious  in  its  development.  It  may  develop 
rapidly  and  without  any  premonitory  symptoms. 
When  established  there  is  intense  circumcorneal  injec- 
tion, an  inflamed  iris,  contracted  pupil,  punctate  depos- 
its upon  Descemet's  membrane,  lowered  vision,  opaci- 
ties in  the  vitreous,  intense  neuralgic  pain  in  the  region 
supplied  by  the  fifth  nerve ;  also  pain  upon  pressure  over 
the  ciliary  region.  The  ophthalmoscope  may  reveal 
a  swollen  disc  and  edematous  retina.  The  iris,  ciliary 
body,  and  choroid  are  involved  in  a  chronic  plastic 
uveitis  which  usually  results  in  total  blindness.  As  the 
disease  progresses,  synchysis  of  the  vitreous,  detach- 
ment of  the  retina,  and  atrophy  of  the  ball  will 
develop. 

Cause. — The  cause  is  an  inflammation  of  the  uveal 
tract  of  the  exciting  eye.  The  uveitis  may  be  idio- 
pathic,   but   the  inflammation   most   prone   to   excite 


l6o  LESSONS    ON    THE    EYE. 

sympathetic  trouble  is  that  due  to  a  wound  ui  the  cihary 
region  or  the  presence  of  a  foreign  body  in  the  exciting 
eve.  Other  sources  of  the  exciting  uveitis  are  perfo- 
rating corneal  ulcers  and  intra-ocular  tumors.  After  an 
enucleation  the  optic  nerve  or  cihary  nerves  being  caught 
in  the  cicatrix  ha\'e  been  known  to  give  rise  to  sympa- 
thetic irritation.  Sympathetic  inflammation  may  arise 
at  any  time  from  tw^o  weeks  to  many  years  after  the 
lesion  of  the  exciting  eye.  Sympathetic  irritation  may 
appear  sooner.  In  spite  of  many  theories,  our  knowl- 
edge of  how  this  inflammation  is  conveyed  from  one 
eye  to  the  other  is  yet  speculative.  It  is  probable 
that  the  condition  in  the  exciting  eye  is  a  proliferative 
uveitis  (Fuchs),  and  that  the  infection,  which  is  patho- 
genic for  the  eye  alone,  is  conveyed  through  the  blood 
to  the  sympathizing  eye  (Romer) . 

Treatment. — As  sympathetic  irritation  is  always 
cured  by  enucleating  the  exciting  eye,  this  should  be 
done  at  once,  but  if  sympathetic  inflammation  is  estab- 
lished this  procedure  will  rarely  stop  it  and  should  not 
be  resorted  to  if  the  exciting  eye  has  useful  vision,  as  it 
will  often  retain  the  best  vision  of  the  tw^o.  If,  in  sym- 
pathetic inflammation,  the  exciting  eye  is  bhnd,  enucle- 
ate it.  Its  removal  may  do  some  good  and  can  do  no 
harm.  The  patient  should  be  kept  in  a  dark  room, 
hot  fomentations  used  four  or  five  times  a  day,  ano- 
dynes given  for  pain,  and  mercury  and  tonics  given 
internally.  Atropin  and  dionin  should  be  used  as  in 
jilastic  iritis.  Sahcylate  of  soda  to  the  limit  of  tolera- 
tion has  been  very  successful  in  some  cases.  As  the 
treatment  of  sympathetic  inflammation  is  so  unsatis- 
factory,  its    prophylaxis   becomes    doubly   im]:)ortant, 


DISKASKS    OI-    THK    VITRKOUS.  l6l 

therefore  it  is  cuh'isaltle  to  enueleate  all  blind  eyes 
affeeted  with  ehronie  irido-eyelitis;  all  eyes  with  irido- 
cyclitis due  to  the  presence  of  a  foreign  body,  which 
cannot  be  removed,  even  if  some  vision  remains;  also 
all  shrunken  globes  and  stumps  which  are  tender  on 
pressure. 

DISEASES  OF  THE  MTREOUS. 

MUSC.-E   VOLITAXTES. 

The  \-itreous  consists  of  98.5  per  cent,  water  and  1.5 
|)er  cent,  of  a  reticulated  framework  of  very  fine  fibers, 
within  the  meshes  of  whiqh  are  found  connective  tissue 
cells  and  migratory  leucocytes.  These  normal  cells  of 
the  vitreous  sometimes  become  so  apparent  as  to  cause 
considerable  annoyance.  They  appear  as  spots  in  front 
of  the  eye  which  may  assume  a  great  variety  of  shapes. 
They  are  most  apparent  when  the  patient  looks  toward 
some  bright  background,  such  as  the  blue  sky  or  a  sheet 
of  white  paper.  Vision  will  be  normal  and  an  examina- 
tion with  the  ()i)hthalm()SC()]je  will  reveal  no  opacities  or 
any  other  pathologic  condition.  It  is  difficult  to  explain 
why  the  shadow  of  these  fixed  cells  will  give  more  annoy- 
ance at  one  time  than  another.  These  periods  of 
annoyance  seem  to  depend,  in  a  measure,  upon  faulty 
digestion,  and  patients  will  often  associate  them  with 
"biliousne-ss."  The  treatment  consists  in  correcting 
any  refracti\-e  error  and  any  defect  in  digestion,  also 
impressing  the  patient  with  the  harmlessness  of  the  con- 
dition and  urging  upon  him  the  necessity  for  disregard- 
ing the  sym])toms. 


1 62  LESSONS    ON    THE    EYE. 

OPACITIES  OF  THE   VITREOUS. 

Vitreous  opacities  may  appear  as  fine  dust,  fiocculi, 
threads,  flakes,  large  masses,  or  membranes.  If  the  vit- 
reous has  become  fluid  (synchysis)  the  opacities  will 
change  their  position  with  every  movement  of  the  eye. 

Symptoms. — The  patient  will  complain  of  lowered 
vision,  which  will  be  found  relatively  worse  for  distance 
than  for  near.     He  will  see  spots  in  the  field  of  vision 


Fig.  log. — Opacities  of  the  vitreous,  dust-like  at  the  lower  pari  of  the 
with  threads  and  membranous  masses  above.     (Jackson.) 


which  correspond  in  size,  shape,  and  position  with  the 
opacities  which  cause  them.  If  the  vitreous  is  fluid, 
vision  will  be  best  when  the  eye  is  kept  still  long 
enough  to  allow  the  opacities  to  settle.  Opacities  of 
the  vitreous  can  only  be  seen  objectively  with  the 
ophthalmoscope. 

Cause. — The  opacities  are  inflammatory  exudates  or 
hemorrhages  which  originate  in  diseases  of  the  ciliary 
body,  choroid,  or  retina.  The  fine  dust-like  opacities 
found  in  the  posterior  part  of  the  vitreous  are  due  to 
syphilitic  involvement  of  the  retina  and  choroid. 
Large  black  masses  are  often  caused  by  the  choroiditis, 
which  is  associated  with  high  degrees  of  myopia.     Gout, 


DISEASKS    OF    TIIK    VIIKKOUS.  163 

tuberculosis,  malaria,  and  senility  are  considered  pre- 
disposing causes. 

Treatment. — Small  and  recent  opacities  may  be 
cleared  up,  but  if  they  are  large  or  of  long  standing  there 
is  little  prospect  of  a  cure.  Diaphoresis  induced  by 
pilocarpin  injections  is  advised.  Also  purging  with 
salines.  Dionin  is  a  powerful  local  lymphagogue  and 
might  prove  of  value.  Main  reliance  is  placed  in  the 
constitutional  treatment  and  mercury  and  potassium 
iodid  have  proven  the  best  remedies  we  possess. 

HEMORRHAGE  IXTO  THE  VITREOUS. 

Symptoms. — If  the  hemorrhage  is  small  the  result 
will  be  a  clot  in  the  vitreous  amounting  to  an  opacity, 
the  symptoms  of  which  have  already  been  given. 
Vision  will  depend  upon  the  amount  of  blood  emptied 
into  the  vitreous.  If  the  hemorrhage  is  pronounced 
vision  will  be  reduced  to  the  perception  of  Hght  and  the 
light  will  appear  red.  At  times  even  light  perception 
is  lost.  When  the  vitreous  is  permeated  with  blood  the 
diagnostic  value  of  the  ophthalmoscope  is  lost,  as  every- 
thing beyond  the  lens  appears  black.  The  iris  and  cili- 
ary body  may  become  inflamed  and  glaucoma  is  not  an 
infrequent  result. 

Cause. — Rupture  of  a  blood  vessel  of  the  ciliary  body, 
choroid,  or  retina  from  traumatism  or  disease. 

Treatment. — If  the  hemorrhage  seems  to  be  sponta- 
neous, absolute  quiet  and  the  internal  administration  of 
such  remedies  as  gallic  acid  or  ergot  may  be  of  service. 
An  effort  should  be  made  to  produce  absorption  of  the 
clot,  to  which  purpose  the  treatment  for  vitreous  opaci- 


164  LESSONS    ON    THE    EYE. 

ties  is  a])])licablc.  If  the  hemorrhage  is  ])rofuse  the 
prospect  is  not  flattering.  Recurring  vitreous  hemor- 
rhage is  exceedingly  dangerous  to  vision.  In  a  few- 
cases  of  recurring  hemorrhage  in  both  eyes,  bHndness 
being  imminent,  the  common  carotid  has  been  hgated 
with  beneficial  results. 


FOREIGN   BODIES  IN  THE  VITREOUS. 

Foreign  bodies,  such  as  splinters  of  wood,  lead  shot, 
small  stones,  particles  of  metal,  and  fragments  of  glass, 
may  be  accidently  driven  into  the  vitreous.  The 
wound  of  entrance  may  be  destructively  large  or  so 
insignificant  that  it  is  hard  to  find.  It  is  often  very 
difficult  to  determine  positively  that  a  foreign  body  is 
present.  The  X-ray  is  of  great  value  in  such  cases.  As 
a  general  proposition  it  may  be  said  that  the  foreign 
body  or  the  eye  must  be  removed.  Particles  of  iron  and 
steel  may  be  removed  by  the  electro-magnet.  A  dia- 
magnetic  body  must  be  withdrawn  with  forceps  or 
carried  out  with  the  vitreous  which  escapes  through  an 
incision  made  as  near  as  possible  to  the  point  where  the 
foreign  body  is  lodged. 


LESSON   XXII. 

DISEASES  OF  THE  CHOROID. 

The  function  of  the  choroid  is  to  nourish  the  retina 
and  vitreous,  and  to  prevent  ;-eflection,  by  the  power  to 
absorb  li^^ht  possessed  by  its  pigment.  In  albinos  there 
is  almost  a  total  absence  of  pigment  in  the  uveal  tract, 
and  great  distress  from  photophobia  is  the  result. 
Albinos  are,  as  a  rule,  afflicted  with  amblyopia,  refract- 
ive errors,  or  nystagmus.  Dark  glasses  are  often  a 
necessity  to  these  patients. 

CHOROIDITIS. 

Choroiditis  is  either  plastic  or  purulent.  The  plastic 
form  may  be  divided  into  disseminate,  central,  syphil- 
itic choroido-retinitis  and  myopic  choroiditis.  When 
purulent  choroiditis  results  in  inflammation  of  all  the 
structures  of  the  eye,  and  this  is  its  usual  termination, 
it  is  called  panophthalmitis. 

PLASTIC    OR    EXUDATIVE    CHOROIDITIS. 

Symptoms. — If  the  morbid  process  is  limited  to  the 
choroid,  external  signs  of  inflammation  are  absent. 
Visual  disturbance  will  be  the  only  subjective  symp- 
tom. The  objective  symptoms  are  revealed  by  the 
ophthalmoscope.  There  may  be  one  or  more  areas  in 
the  field  of  vision  in  which  objects  are  seen  dimly 
or  not  at  all.  These  areas  are  called  scotomata. 
If  vision  is  only  diminished  in  a  scotoma,  it  is 
165 


l66  LESSONS    ON    THE    EYE. 

said  to  be  relative;  if  it  is  entirely  absent,  the 
scotoma  is  positive.  Vision  may  be  reduced  by  a 
diffuse  cloudiness  of  the  vitreous,  or  if  opacities  have 
formed  in  it  there  may  be  movable  dark  spots  in  the 
field.  Night  blindness  is  a  frequent  symptom  (page 
2x4).  Patients  may  complain  of  sparks  or  lights  before 
their  eyes.  There  may  also  be  distortion  of  the  outline 
of  objects  called  metamorphopsia.  For  example,  in 
metamorphopsia  a  series  of  parallel  lines  will  appear 
wavy  in  places,  or  when  reading,  a  word  in  a  line  will 
appear  above  or  below  its  normal  position.  If  the 
choroidal  exudate  causes  a  separation  of  the  percipient 
elements  of  the  retina  objects  will  appear  unnaturally 
small,  a  condition  called  micropsia.  Megalopsia,  a 
condition  in  which  objects  look  unnaturally  large,  is 
produced  by  shrinkage  of  the  exudate.  If  the  in- 
flammatory process  is  limited  to  the  periphery  of  the 
choroid  there  may  be  no  subjective  symptoms  whatever. 
The  visual  disturbance  will  depend  upon  the  prox- 
imity of  the  inflamed  area  to  the  macula  and  the 
amount  of  involvement  of  the  vitreous. 

The  ophthalmoscope  will  show,  in  recent  cases,  ill- 
defined  yellowish  patches  under  the  retinal  vessels. 
These  spots  of  exudation  may  absorb  and  leave  no 
sign,  but  generally  the  choroid  at  these  points  atrophies 
and  the  sclera  shows  glistening  white  through  it. 
Around  the  borders  of  these  atrophic  areas,  pigment  is 
soon  deposited.  The  retina  over  the  inflamed  area  is 
usually  invoU^ed  and  also  partakes  of  the  subsequent 
atrophy,  which  explains  the  scotomata  or  blind  spots 
in  the  field  of  vision.  The  inflammatory  process  may 
extend  to  the  vitreous  and  cause  a  cloudiness  of  that 


DISEASES    OF    THE    CHOROID.  1 67 

ImkIv,  at  times  SO  (k-nse  as  to  prcx-enl  an  oj)luhalnio- 
scopic  view  of  the  underlying  tissues. 

Cause. — Syphilis,  malnutrition,  serofnla,  infection, 
anemia,  a  blow  upon  the  eyeball,  high  myopia,  and 
in  some  cases  no  cause  can  be  assigned  with  any  degree 
of  accuracy.  The  choroid,  being  a  part  of  the  uveal 
tract,  is  subject  to  inflammation  arising  in  the  iris  and 
ciliary  body. 

Treatment. — Absolute  rest  of  eyes  and  the  use  of 
mydriatics,  smoked  glasses,  mercury,  iodid  of  potas- 
sium, and  tonics. 


Fig.  1 10. — Choroiditis  disseminata.     The  macular  region  not  being  involved, 
central  vision  n^ight  be  nornril.     (After  De  Wecker.) 

Disseminate  choroiditis  is  the  form  inflammation  of 
the  choroid  is  most  likely  to  assume.  As  the  name  indi- 
cates, there  is  a  general  involvement  of  the  choroid. 
There  will  be  a  number  of  areas  of  exudation  or  atrophy, 
depending  upon  the  stage  of  the  disease,  scattered 
over  the  fundus.     As  long  as   the  macular  region   is 


t68  lessons  on  the  eye. 

not  involved,  central  N'ision  may  remain  good.  There- 
fore disseminate  choroiditis  may  be  far  advanced  be- 
fore the  patient  is  conscious  of  any  eye  trouble.  Its 
course  is  chronic.  Treatment  may  check  the  disease, 
but  cannot  restore  the  function  of  the  atrophic  areas. 
Central  choroiditis  involves  the  macular  region.  It 
may  consist  of  one  large  inflammatory  area  or  several 


Fig.  III. — Central  chon>i(litis.     (\\'ccl<cr  and  Jaeger.) 

smaller  ones.  Direct  vision  is  impaired  or  lost  and 
there  is  a  central  scotoma  in  the  field  of  virion.  Central 
choroiditis  is  often  due  to  myopia  of  high  degree  or  to 
seniHty.  The  discovery  of  a  central  choroiditis  after 
the  removal  of  a  cataract  is  a  disagreeable  surprise  to 
patient  and  operator. 

Syphilitic  choroido-retinitis  is  a  diffuse  inflammation 
of  the  choroid  and  retina.  The  fundus  involvement  is 
both  central  and  peripheral.  Whether  the  disease  is 
primarily   choroidal   or  retinal  is   an   open   question. 


DISEASKS    OF    THE    CHOROID.  1 69 

The  retina  will  appear  opaque  and  edematous  and 
under  it  can  be  seen  the  numerous  yellow  spots  charac- 
teristic of  choroidal  exudation.  A  fine, dust-like  opacity 
in  the  posterior  part  of  the  vitreous  is  usually  present. 
It  may  be  so  dense  as  to  prevent  a  clear  \iew  of  the 
fundus  and  also  interfere  with  the  patient's  vision.  If 
seen   earl V,  the   disease   will   respond    satisfactorily   to 


Fig.  112. — .\tr()phy  after  syphilitic  choroiditis,  showing  various  degrees 
of  wasting,  a,  .\trophy  of  pigment  epithelium;  b,  .Atrophy  of  epithelium  and 
chorio-capillaris;  the  large  vessels  exposed;  c,  Spots  of  complete  atrophy, 
many  with  pigment  accumulation. 

vigorous  mercurial  medication.  In  the  later  stages, 
when  there  are  atrophic  spots  in  the  choroid  and  retina, 
treatment  can  at  best  only  check  the  disease. 

Myopic  choroiditis  presents  two  characteristic  pic- 
tures. One  or  both  may  be  present.  They  are:  (i) 
A  well-defined  white  crescent  on  the  temporal  side  of 
the  disc,  and  (2)  central  choroiditis.  The  elongation 
of    the   antero-posterior   axis   found    in    myopia,    par- 


I70 


LESSONS    ON    THE    EYE. 


ticularly  in  the  in'ogressive  form,  is  due  to  a  protrusion 
backward,  of  the  sclera,  called  posterior  staphylouia. 
This  bulging  of  the  sclera  stretches  the  choroid  at  the 
temporal  side  of  the  disc.  The  atrophy  of  the  choroid 
which  follows  allows  the  white  sclera  to  show  through, 
producing  the  "myopic  crescent."  At  times  the  atrophic 
area  encircles  the  disc,  but  it  is  most  prominent  on  the 
temporal  side.     When  the  margin  of  the  crescent  is 


Fig.  113.- M 


sharply  outlined  and   pigmented  it  usually   indicates 
that  the  myopia  has  ceased  progressing. 

Myopia  of  high  degree  will  usually  produce  choroidal 
changes  other  than  the  myopic  crescent.  These  exuda- 
tive and  atrophic  spots  may  be  found  in  any  ])art  of  the 
fundus,  but  they  are  almost  invariably  located  at  the 
macular  region.     See  Central  Chroroiditis ;  page  168. 


DISEASES    OF    THE   CHOROID.  171 


PURULEXT    CHOROIDITIS. 


Cases  of  purulent  choroiditis  may  present  widely  dif- 
ferent symptomatic  pictures,  varying  from  an  asthenic 
form  which  develops  without  the  consciousness  of 
the  patient  (pseudo-glioma)  to  a  violent  and  excruci- 
atingly painful  variety  (panophthalmitis).  The  symp- 
toms common  to  all  cases  are  suppuration  of  the  choroid, 
total  loss  of  vision  and  shrinkage  of  the  eyeball. 

In  rare  instances,  particularly  in  children,  suppura- 
tion of  the  choroid  may  not  be  attended  by  any  external 
evidences  of  inflammation.  The  first  knowledge  of 
the  disease  may  be  furnished  by  the  appearance  of  a 
yellow  reflex  from  the  pupil,  which  is  usually  dilated. 
This  reflex  is  from  pus  in  the  vitreous.  The  condition 
is  called  pseudo-glioma  and  is  dift'erentiated  from 
true  glioma  in  the  early  stage  with  difficulty.  Vision 
is  permanently  lost  and  shrinkage  of  the  ball  follows. 

The  symptoms  usually  manifested  by  purulent 
choroiditis  are  swelling  of  the  lids,  chemosis  of  the 
conjunctiva,  early  loss  of  vision,  severe  pain,  and  prob- 
ably a  rise  in  temperature.  If  the  process  begins  in  an 
ulcer  or  wound  of  the  cornea,  this  tissue  will  soon  become 
opaque  and  suppurative.  If  the  lesion  starts  from 
within,  the  iris  will  change  color,  as  in  iritis,  and  the 
aqueous  become  muddy;  but  in  spite  of  this,  the  yellow 
reflex  caused  by  pus  behind  the  lens  may  generally  be 
seen.  In  a  few  weeks  the  severe  inflammation  sub- 
sides, tension  of  the  ball  becomes  minus,  and  atrophy 
begins. 

In  the  severest  form  (panophthalmitis),  all  of  the 
above  symptoms  increase  in  intensit}".     The   jjain   is 


172  LESSONS    ON    THE    EYE. 

excruciating.  There  is  rise  of  temperature  with  vomit- 
ing. Tenon's  capsule  becomes  inflamed  and  thickened, 
causing  exophthalmos  and  loss  of  motion.  The  eyeball 
will  perforate  and  the  pus  escape.  When  this  happens 
the  pain  and  other  symptoms  rapidly  subside,  to  be 
followed  by  shrinkage  of  the  ball  to  a  small  stump 
(phthisis  bulbi). 


Fig.  114. — Two  ruptures  in  the  choroid,  (.\fter  Knapp.)  The  retinal  ves- 
sels pass  unbroken  across  the  rupture.  The  dark  spot  to  the  right  is  a 
hemorrhage. 


Cause. — Intra-ocular  pus  infection  from  wounds, 
operations,  perforating  ulcers  of  the  cornea,  pyemia  by 
metastasis  or  meningitis. 

Treatment. — Control  the  pain  by  leeches,  hot  bichlorid 
fomentations  and  anodynes,  and  enucleate  as  soon  as 
convinced  that  the  eye  is  lost.  E\'isceration  is  pre- 
ferred by  some  as  offering  less  danger  of  setting  up  a 
meningitis  than  enucleation.  If  thorough  evisceration 
is  not  deemed  advisable,  a  simple  incision  through  the 
sclera,  to  let  out  the  pus,  may  be  made  and  enucleation 


DISKASKS    OF    TIIK    C'HOROIP.  I  7^ 

j^ustponcd    until    the    inllammatt)ry    symptoms    have 
subsided. 

RUPTURE    OF    THE    CHOROID. 

A  blow  upon  the  eye  may  cause  a  rupture  of  the 
choroid.  Hemorrhage  into  the  vitreous  will  usually  pro- 
duce a  temporary  loss  of  \'ision  and  prevent  a  view  of 
the  fundus.  When  the  blood  is  absorbed  a  long  white 
crescent-shaped  streak  will  be  found  usually  not  far 
from  the  temporal  side  of  the  disc.  If  the  retina  is  not 
injured  its  blood  vessels  will  course  normally  over  the 
lesion  in  the  choroid.  Permanent  loss  of  vision  will 
depend  upon  the  proximity  of  the  rupture  to  the  mac- 
ular region. 

Tumors  of  the  Choroid. — Sarcoma,  jjigmented  and 
unpigmented.  frequently  develops  in  the  choroid.  It 
may  be  primary  or  metastatic,  nearly  always  the  for- 
mer. In  the  early  stages  sarcoma  must  be  differen- 
tiated from  detachment  of  the  retina  and  later  from 
glioma.  Carcinoma  of  the  choroid  has  been  observed. 
It  is  usually  metastatic.  Tuberculosis  of  the  choroid  may 
take  the  form  of  numerous  small  yellowish  spots  (mili- 
ary tubercles)  or  present  but  one  large  tubercle. 


LESSON  XXIII. 

GLAUCOMA. 

The  vitreous  and  crystalline  lens,  being  non-^•ascular 
bodies,  are  nourished  by  lymph.  This  lymph  is  se- 
creted by  the  choroid,  the  vascular  part  of  the  ciliary 
body,  and  the  posterior  surface  of  the  iris.  The  proc- 
ess of  secretion  being  continuous,  there  must  be  a 
coincident  excretion,  and  we  find  this  takes  place  in 
the  angle  of  the  anterior  chamber,  through  the  spaces 
of  Fontana,  which  connect  with  the  canal  of  Schlemm. 
The  direction  of  the  current  is  from  the  vitreous,  around 
the  lens,  into  the  posterior  aqueous  chamber,  thence 
through  the  pupil  into  the  anterior  aqueous  chamber, 
thence  through  the  spaces  of  Fontana  and  canal  of 
Schlemm  into  the  anterior  ciUary  veins.  It  is  also 
claimed  that  some  of  the  aqueous  fluid  is  absorbed 
through  the  crypts  in  the  anterior  surface  of  the  iris. 
Normal  intraocular  tension  is  dependent  upon  the 
maintenance  of  a  physiologic  balance  between  the  secre- 
tion and  excretion  of  the  aqueous  humor. 

The  normal  resistance  of  the  globe,  when  palpated 
l)v  the  index  finger  of  each  hand,  is  designated  by  the 
letters  Tn.  If  the  globe  is  abnormally  hard  its  in- 
creased tension  is  designated  relatively  by  the  signs  T  +, 
T  +1,  T-h2,  and  T+3.  If  abnormally  soft,  by  T-, 
T-i,  T-2,  and  T-3. 

Glaucoma  is  a  diseased  condition,  supposed  to  be 

174 


GLAUCOMA. 


'75 


due  U)  rxccssi\-e  intni-ocular  pressure,  ll  may  be 
i(li()l)athic  or  secondary  to  some  other  pathologic  con- 
dition of  the  eye.  Idiopathic  or  primary  glaucoma 
may  be  simple  or  inflammatory.  The  inflammatory 
form  is  usually  divided  into  acute,  sub-acute,  and 
chronic  \-arieties.  All  forms  of  primary  glaucoma 
are  pathologically  the  same  disease,  the  different 
aspects   presented   being   due   to   different  degrees   of 


Fig.  115. — Ophthalmoscopic  appearance  of  a  glaucomatous  excavatkin   of 
the  disc. 


intensity.  The  symptoms  of  a  mild  form  (simple 
glaucoma),  and  a  severe  manifestation  (acute  inflam- 
matory glaucoma)  will  be  given;  it  being  understood 
that  the  disease  may  assume  innumerable  types,  vary- 
ing in  intensity,  between  the  two.  It  must  be  remem- 
bered that  glaucoma  is  generally  a  disease  of  relapses 
and  remissions  which  will  eventuate  in  total  blindness. 
Both  eyes  are  usually  involved,  but  one  may  be  attacked 
months  or  even  years  before  the  other. 


176 


LESSONS    ON    THE    EYE. 


Symptoms  of  Simple  Glaucoma. — The  patient  will  prob- 
ably first  notice  a  failure  in  vision  for  near  work — an 
unnatural  presb^^opia,  which  will  necessitate  the  use 
of  convex  lenses  at  an  unusually  early  age,  or  require 
lenses  stronger  than  the  age  of  the  patient  would  natur- 
ally demand.  Artificial  Hghts  may  be  surrounded  by 
halos  or  colored  rings.  At  times  a  mist  seems  to  ob- 
scure vision,  and  occasionally  the  patient  will  find 
himself  in  total  darkness  for  several  seconds.     A  slight 


temporal 


Fig.  1 1 6. — Longitudinal  section  through  a  glaucomatous  optic  nerve. 
Deep  excavation,  e;  remains  of  nerve  fibers,  b;  choroid,  ch;  sclera,  s;  nerve 
fibers,  n;  pia  mater,  p;  arachnoid,  ar;  dura  mater,  d;  central  artery  of  the 
retina,  c:  retina,  r.     (Fuchs.) 


dull  pain  of  a  neuralgic  character  may  or  may  not  be 
felt  in  and  around  the  ball.  The  eye  generally  appears 
normal  except  for  a. slight  dilatation  of  the  pupil,  the 
possible  existence  of  an  unusual  whiteness  of  the 
sclera  and  the  presence  of  a  few  large  and  tortuous 
conjunctival  vessels.  In  the  early  stages  visual  acuity 
may  or  may  not  be  reduced,  but  the  field  of  vision 
will  most  likely  show  peripheral  contraction,  greatest 
on  the  nasal  side,  and  scotoma  may  exist.  Tension  of 
the  ball  will  be  increased,  with  periodic  variations  in 


GLAUCOMA.  177 

degree,  at  times  approximating  so  closely  to  the  normal 
that  its  glaucomatous  nature  may  not  he  appreciable. 
If  the  disease  has  existed  for  some  time,  the  charac- 
teristic cupping  or  excavation  of  the  optic  disc  will  be 
seen.  If  tension  is  appreciably  high,  there  may  be 
spontaneous  pulsation  of  the  retinal  arteries.  Patients 
suffering  with  simple  glaucoma  often  consult  a  ])hysican 
only  because  vision  is  impaired  and  arc  unconscious  of 


Fig. 


-Angle  of  the  anterior  chamt 


)rmal  eye.      (Birnhacher.) 


the  presence  of  any  pathologic  condition.  Simj^le 
glaucoma  ma\'  slowly  deprive  its  victim  of  sight  without 
manifesting  any  symptoms  more  acti\'e  than  those 
detailed,  but  it  frequently  changes  into  the  inflam- 
matory type.  Simple  glaucoma  always  attacks  both 
eyes,  but  rarely  at  the  same  time.  It  sometimes  occurs 
in  young  people  and  may  be  found  in  myopic  eves, 
which  seem  to  be  more  or  less  immune  to  inflamma- 
tory glaucoma. 

Symptoms  of  Acute  hifiannnatory  (JlaiiLonia. — The 
attack  comes  on  suddenly  and,  as  a  rule,  at  night.  It 
may  or  may  not  have  been  preceded  by  premonitory 


lyS  LESSONS    ON    THE    EYE. 

symptoms,  such  as  failure  of  vision  for  near  work,  the 
presence  of  colored  rings  around  lights,  and  temporary 
obscurations  of  sight.  The  true  nature  of  the  attack 
may  be  overlooked,  owing  to  the  severe  pains  in  the 
head  and  face  and  the  probable  presence  of  an  increase  in 
pulse  and  temperature  with  vomiting.  It  may  be 
mistaken  for  a  severe  "bilious  attack,"  the  inflamed 
eye  being  considered  incidental.  Tension  of  the  globe 
is  markedly  increased,  the  lids  edematous,  the  con- 
junctiva injected  and  chemotic.  The  cornea  will 
be  more  or  less  opaque  or  steamy  and  anesthetic,  the 
anterior  chamber  shallow  and  its  contents  possibly 
cloudy  from  the  presence  of  lymphoid  cells.  The 
pupil  will  be  widely  dilated,  and  the  normal  black 
reflex  may  be  green.  The  interior  of  the  eye  will 
probably  not  be  visible,  owing  to  the  opacity  of  the 
cornea,  but  if  the  fundus  can  be  viewed  the  veins  will 
appear  distended  and  sinuous  and  the  arteries  will  be 
small  and  show  pulsation.  If  glaucoma  has  not  pre- 
viously existed  the  disc  wdll  probably  not  be  excavated, 
but  it  will  appear  soon  if  the  high  tension  continues. 
Vision  will  of  course  be  greatly  reduced.  The  symp- 
toms may  be  so  intense  as  to  destroy  the  eye  in  a  few 
hours,  in  which  case  the  disease  is  called  glaucoma 
fulminans.  As  a  rule,  the  symptoms  abate  and  the 
eye  may  return  almost  to  the  normal  in  appearance, 
without,  however,  a  return  of  the  pre-existing  visual 
acuity.  After  the  lapse  of  a  variable  period  another 
attack  supervenes,  resulting  in  an  additional  loss  of 
vision,  and  so  the  disease  progresses  until  the  absolute 
state  is  established  and  blindness  results. 

In  absolute  glaucoma  the  ball  is  hard,  ]X'iin  constant 


GLAUCOMA.  179 

and  intense,  the  lens  eataractous  and  pushed  forward. 
The  pupil  is  widely  dilated  and  fixed.  The  selera  is 
bluish  in  color,  with  a  dusky,  red,  circumcorneal  zone, 
caused  by  engorgement  of  the  anterior  cihary  veins. 
The  cornea  is  lusterless  and  vision— even  light  percep- 
tion— is  gone. 

Further  changes  through  w^hich  the  eye  may  pass  are 
degenerative.     There  may  be  ulceration  of  the  cornea 


Fig.  118. — Angle  of  the  anterior  chamber  in  glaucoma  closed  by  adhesion  of 
iris  base  to  the  periphery  of  the  cornea.    (Rirnbacher.) 

with  perforation,  followed  by  panophthalmitis  and 
phthisis  bulbi.  The  sclera  may  give  way  and  staphy- 
loma result ;  or  the  eye  may  slowdy  atrophy  as  a  result 
of  choroiditis,  changes  in  the  vitreous  and  detachment 
of  the  retina. 

Cause. — In  general  terms  hypersecretion  or  sub-nor- 
mal excretion  of  the  intra-ocular  fluid  are  responsible  for 
the  train  of  symptoms  called  glaucoma.  Blocking  up 
the  angle  of  the  anterior  chamber  (Fig.  118)  by  di- 
minishing excretion,  is  undoubtedly  a  potent  factor  in 
the  production  of  the  disease.  The  use  of  a  mydriatic, 
by  dilating  the  pupil,  pushes  the  iris  into  the  filtration 


l8o  LESSONS    ON    THE    EYE. 

angle,  and  will  sometimes  bring  on  an  attack.  The 
iris  is  supposed  to  be  forced  forward  in  such  a  way  as  to 
partially  block  the  spaces  of  Fontana,  when  a  large 
lens  is  associated  with  a  small  hyperopic  eye.  That 
this  has  something  to  do  with  the  production  of  glau- 
coma seems  plausible  when  we  consider  that  the  lens 
continues  to  grow  until  the  sixty-fifth  year  and  that 
about  70  per  cent,  of  all  cases  occur  after  the  age  of  fifty 
and  the  same  per  cent,  are  found  in  hyperopic  eyes.  An 
exacerbation  may  be  excited  by  fatigue,  grief,  worry, 
or  anything  which  lowers  vitality.  Among  the  sup- 
posed etiological  factors  heredity,  rheumatism,  and 
disturbances  of  circulation  may  be  mentioned.  Secon- 
dary glaucoma  may  be  directly  attributable  to  intra- 
ocular hemorrhage,  complete  anterior  or  posterior 
synechia,  traumatic  cataract  with  rapid  swelling  of 
the  lens,  intra-ocular  tumors,  etc. 

Treatment. — As  soon  as  positive  of  the  diagnosis,  do  a 
broad  iridectomy.  This  procedure  is  the  most  cura- 
ti\'e  measure  at  our  disposal.  Though  introduced  in 
1856  by  Von  Graefe,and  practised  ever  since  that  time, 
we  do  not  yet  know  exactly  how  it  produces  the  amelio- 
ration which  follows  in  so  many  cases.  The  results  of 
this  operation  are  much  better  in  cases  of  inflammatory 
glaucoma  than  in  the  non-inflammatory  type. 

The  operation  of  sclerotomy  is  favored  by  some. 
The  incision  of  anterior  sclerotomy  is  made  just  in  front 
of  the  iris.  In  posterior  sclerotomy  it  is  between  the 
ciliary  body  and  equator.  Removal  of  the  superior 
cervical  ganglion  was  introduced  by  Jonnesco.  This 
operation  has  checked  the  progress  of  the  disease  in  a 
number   of    reported    cases.     Lagrange    combines    an 


{'.LAUCOMA.  161 

iriclcctoni}-  with  rciiKnal  of  a  small  sector  c^f  the  sclera. 
The  purpose  being  to  establish  a  filtrating  scar.  The 
operation  of  cyclodialysis  consists  in  establishing  a 
direct  communication  between  the  anterior  chamber 
and  the  supra-choroidal  space  (Heine).  Its  efTficacy 
has  not  yet  been  determined.  If  any  constitutional 
condition  exists  which  may  be  a  factor  in  the  produc- 
tion of  the  glaucoma,  it  should  receive  appropriate 
treatment.  The  local  medicinal  treatment  is  practi- 
cally limited  to  the  use  of  the  miotics,  eserin  and  pilo- 
carpin.  The  sulfate  or  salicylate  of  eserin,  is  used  in 
strength  varying  from  1/4  to  2  grains  to  §i.  Pilo- 
carpin  may  be  used  twice  as  strong.  The  frecjuency  of 
instillation  is  determined  by  their  effect  on  the  pui)il. 
The  miotics  find  their  greatest  field  of  usefulness  in 
the  non-inflanimatory  forms  of  glaucoma.  Their 
judicious  use  will  sometimes  control  this  type  of  disease 
for  years.  For  the  pain  use  hot  fomentations  and 
anodynes. 

Dionin,  according  to  Darier,  acts  as  a  decided  anal- 
gesic in  glaucoma.  He  uses  it  in  the  same  solution 
with  the  miotics.  He  also  claims  that  the  tension  is 
favorably  influenced  by  gentle  massage  of  the  ball 
through  the  closed  lid.  Few  diseases  have  claimed  as 
much  attention  of  investigators  and  writers  as  glau- 
coma; in  spite  of  which  its  etiology  is  unsettled  anfl 
its  treatment  often  hopelessly  disappointing. 


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LESSON  XXIV. 

DISEASES  OF  THE  CRYSTALLINE  LENS. 

DISLOCATION  OF  THE   LENS. 

This  condition  may  exist  congenitally  or  may  be  due 
to  accident  or  disease.  The  lens  may  be  partially  held 
by  the  suspensory  ligament  or  may  be  totally  detached. 
The  dislocation  may  be  to  the  side,  back  into  the  vitre- 
ous or  forward,  through  the  pupil,  into  the  anterior 
chamber.     If  due  to  disease,  it  is  associated  with  cho- 


FiG.  119. — Downward  dislocation  of  a  cataractous  lens. 

roiditis,  cyclitis,  and  a  fluid  state  of  the  vitreous.  The 
lens  may  be  perfectly  transparent  or  cataractous.  If 
cataractous  the  malposition  may  be  easily  detected 
(Fig.  119).  If  transparent  and  not  in  the  anterior 
chamber,  the  ophthalmoscope  will  re\'eal  the  condition. 
A  transparent  lens  in  the  anterior  chamber  can  be  diag- 
nosed by  close  inspection  with  the  unaided  eye.  Con- 
184 


DISEASES    OK    THE    CRYS  TAELINE    LENS. 


T8:; 


i^cnilal    partial    disloc-alioii   may   l)c   let    alone.      W'Ikmi 
(hie  to  accident  or  disease  it  would  1  letter  be  remo\'ed. 


Opacity  of  the  lens,  or  its  capsule,  or  both,  constitutes 
cataract.  Numerous  terms,  which  explain  themselves, 
are  used  in  classifying  cataracts,  such  as  lenticular,* cap- 
sular, and  capsulo-lenticular;  partial  and  complete; 
traumatic  and  spontaneous;  fluid,  soft,  and  hard;con- 


FiG.  120. — .\,  normal  lens;  P.,  anterior  juilar  cataract ;  C,  posterior  polar 
cataract;  D,  cortical  cataract;  E,  nuclear  cataract;  V,  lamellar  cataract. 
(Juler.) 


genital,  juvenile,  and  senile;  immature,  mature,  and 
hypermature;  .simple  and  comphcated ;  stationary  and 
progressive;  gray,  white,  amber,  and  black. 

Cataracts  are  further  classified  by  terms  which  indi- 
cate the  location  of  the  opacity  as  follows : 

I.  Anterior  polar  cataract,  in  which  the  opacity  is  a 
small  spot  in  the  center  of  the  anterior  capsule,  extend- 
ing into  the  subjacent  lens  substance.  It  is  usually 
pyramidal  in  shape,  and  may  be  congenital  or  acquired 
in  early  infant  life.  When  congenital  it  is  supposed  to 
be  the  result  of  a  fetal  inflammation  in  which  a  deposit 


1 86  LESSONS    ON    THE   EYE. 

of  h'mi)h  was  left  on  the  anterior  capsule;  or  to  be  due 
to  the  adherence  of  the  fetal  ])upillary  membrane  to  the 
capsule.  When  acquired  it  is  due  to  a  perforation  of 
the  cornea  which  has  allowed  the  lens  to  come  foru'ard 
in  contact  with  the  cornea. 

2.  Posterior  polar  cataract,  similar  to  the  preceding, 
except  located  in  the  center  of  the  posterior  capsule.  In 
fetal  Ufa  the  hyaloid  artery  comes  in  contact  with  the 
lens  at  the  posterior  pole.  An  incomplete  clearing  up  of 
the  point  of  contact  would  explain  a  congenital  pos- 


it v. 


Fig.  121. — Nuclear  cataract,      i,  Section  of  lens;  central  position  of  opat 
2,  appearance  by  ophthalmoscope;  appearance  by  oblique  illuminatior 


terior  polar  cataract.  Another  form  of  opacity,  gener- 
ally called  posterior  polar,  but  which  in  reality  lies  in 
the  posterior  cortex,  assumes  the  shape  of  a  star  or 
rosette ;  the  center  of  the  star  corresponding  to  the  pos- 
terior pole  of  the  lens.  It  is  usually  associated  ^yith 
retinal  or  choroidal  disease. 

3.  Lamellar  or  zonular  cataract,  in  whch  the  opacity 
is  confined  to  one  or  more  of  the  layers  of  the  lens.  It 
is  assumed  that  there  is  a  disturbance  of  nutrition  at  a 
period  of  fetal  Hfe  subsequent  to  the  development  of  the 
clear  nucleus.  The  layer  of  lens  substance  developed 
at  the  time  of  the  nutritive  disturbance  is  opaque. 
The  interruption  to  the  normal  development  of  lens 
matter  being  temporary,  the  subsequent  la\-ers  are 
transparent. 


DISEASES    OF   THE    CRYSTALLINE    LENS.  1 87 

4.  Nuclear  cataract,  in  which  the  opacity  begins  in 
the  hard  center  of  I  he  Umis. 

5.  Cortical  cataract,  in  which  the  oi)acity  bci^ins  at 
the  periphery  of  the  lens. 

Symptoms. — In  children,  if  the  cataract  is  complete, 
it  is  easily  diagnosed,  as  the  pupillary  area  will  be  white 
or  gray  and  the  eye  will  be  blind.  If  the  cataract  is 
zonular,  which  is  the  most  frequent  form  in  children, 
and  is  always  congenital  or  arises  in  early  infant  life,  the 
vision  is  much  reduced,  the  child  beha^•ing  as  if  near- 


FiG.  122.— Cortical  cataract,  i,  Section  of  lens;  opacities  beneath  the 
capsule;  2,  Opacities  as  seen  by  the  ophthalmoscope;  3,  Opacities  as  seen  by 
oblique  illumination. 

sighted.  Best  vision  is  secured  when  the  pupil  is  di- 
lated, as  the  patient  can  then  see  around  the  opacity. 
Hence  these  children  w411  shade  their  eyes  or  turn  their 
backs  to  the  light  to  get  better  vision,  and  will  find 
their  sight  improved  by  the  twilight  or  cloudy  weather. 
Close  inspection,  with  the  pupil  dilated,  will  reveal  a 
pale,  round,  central  opacity  of  the  lens;  the  rim  of  the 
opacity  being  denser  than  the  center,  that  will  distin- 
guish it  from  a  nuclear  cataract  which  is  denser  in  the 
center.  It  is  often  found  that  children  with  zonular 
cataracts  have  been  subject  to  infantile  convulsions  or 
are  affected  wdth  rachitis.  Anterior  polar  cataract  is 
easily  detected  by  the  small,  snow-white  speck  seen  in 
the  pupillary  area.  It  does  not  affect  vision  as  much  as 
the  zonular  variety.     The  great  majority  of  cataracts 


1 88  LESSONS    ON    'J-HE    EYE. 

arise  after  the  forty- fifth  year  and  are  caUed  senile  or 
hard .  The  latter  term  is  derixed  from  the  condition  of  the 
nucleus,  which  at  this  age  has  become  quite  dense.  They 
are  usually  nuclear  or  cortical.  As  a  rule,  the  first  symp- 
tom noticed  is  failing  vision,  not  improved  by  glasses. 
In  some  cases,  in  the  first  stages  of  the  disease,  the  opac- 
ity increases  the  index  of  refraction  of  the  lens,  and  thus 
increases  its  refractive  power  sufficiently  to  enable  the 
patient  to  read  without  glasses.  The  patient  rejoices 
in  what  is  commonly  called  second  sight.  Unfortunately, 
this  state  is  temporary  and  gradual  loss  of  vision  follows. 
If  the  cataract  is  nuclear,  vision  is  improved  by  any 
circumstance  which  dilates  the  pupil.  There  is  gener- 
allv  some  hvperemia  of  the  conjunctiva,  lacrymation 
and  itching.  Sometimes  inspection  of  the  pupil  reveals 
no  anomaly,  but  cataract,  in  the  advanced  stages,  shows 
a  distinct  white  or  grayish  appearance  of  the  pupillary 
area.  Oblique  focal  illumination  will  demonstrate 
some  opacities,  but  to  determine  their  presence  in 
doubtful  cases  the  ophthalmoscope  must  be  used. 
With  the  pupil  dilated  the  whole  lens  can  be  brought 
under  inspection  and  the  slightest  opacity  will  be 
detected  by  the  ophthalmoscope.  The  time  between 
incipiency  and  maturity  varies  greatly  in  different  cases, 
and  in  a  few  a  partial  opacity  will  remain  stationary  for 
the  rest  of  life.  A  traumatic  cataract,  due  to  rupture 
of  the  capsule,  may  swell  so  rapidly  from  imbibition  of 
aqueous  humor  as  to  bring  on  glaucomatous  symptoms. 
A  cataract  is  said  to  be  ripe  when  all  the  lens  substance 
is  opaque.  This  may  be  determined  by  throwing  a 
light,  obliquely,  into  the  dilated  pupil.  If  there  is  a 
dark,  crescent-shaped  shadow  on  the  lens,  next  to  the 


DISEASES    OF    THE    CRYSTALLINE    LENS.  1 8g 

iris,  on  the  same  side  as  the  Hght,  there  is  eonsiderable 
lens  substanee  whieh  is  still  transparent.  If  the  entire 
lens  is  opaque,  no  shadow  will  l)e  east  ujion  it  by  the 
margin  of  the  iris. 

Cause. — Cataract  is  supposed  to  be  due  to  some  dis- 
turbance of  the  nutrition  of  the  lens.  It  is  a  degenera- 
tive change,  coming  as  do  gray  hairs,  \'ery  little  being 
known  of  the  conditions  that  conduce  to  it.  Diabetes, 
ergotism,  heredity,  glaucoma,  hyperopia,  and  spasms 
in  children  are  supposed  to  be  etiological  factors.  Glass 
blowers,  stokers,  etc.,  whose  eyes  are  exposed  to  excess- 
ive heat  and  light,  are  supposed  to  be  unusually  sub- 
ject to  the  disease.  Traumatic  cataracts  are  due  to 
some  accident  which  jjunctures  the  capsule  or  loosens 
the  lens  from  its  ligamentous  attachment. 

Treatment. — Spontaneous  absorption  of  the  cataract 
has  been  reported  in  a  few  authenticated  cases,  but  no 
therapeutic  agent  has  yet  been  discovered  that  will 
bring  about  this  happy  result.  The  treatment  is  sur- 
gical. For  the  operations  suited  to  the  different  varie- 
ties consult  a  text-book.  Before  operating  or  recom- 
mending a  case  for  operation  be  sure  to  test  the  bad  eye 
for  other  pathologic  conditions.  Cataract  prevents  the 
distinction  of  objects,  but  does  not  obstruct  light. 
Take  the  patient  into  a  darkened  room  and  with  the 
good  eye  well  covered  see  if  he  can  point  out  the  direc- 
tion of  a  lighted  candle  when  held  in  all  parts  of  the 
field  of  vision.  If  he  can  readily  follow  the  light  his 
retina  and  optic  nerve  are  healthy  and  a  successful 
operation  will  make  him  see  again.  If  he  cannot  see 
the  light  at  all  an  operation  is  useless.  If  he  sees  only 
in  certain  parts  of  the  field  or  detects  slowly  the  diff'er- 


igo  LESSONS    ON   THE    EYE. 

ence  between  light  and  shadow,  an  operation  will  be 
proportionately  meager  of  results. 

An  aphakic  eye  is  one  which  has  no  lens.  The  re- 
moval of  the  crystalline  lens  from  an  emmetropic  eye 
will  make  it  very  hyperopic.  After  a  cataract  operation 
upon  an  emmetropic  eye  a  strong  convex  lens  must  be 


Fig.  123. — Speculum  used  to  hold  the  lids  open  in  operations  upon  the  eyeball. 

worn  to  compensate  for  the  one  removed.  If  the  oper- 
ated eye  was  previously  hyperopic  the  correcting  lens 
will  be  stronger  still ;  if  it  was  m^^opic  the  correcting  lens 
will  be  weaker  than  in  the  case  of  an  emmetropic  eye. 
It  is  possible  for  the  removal  of  the  lens  to  so  neutralize 
a  high  degree  of  myopia  as  to  secure  excellent  vision 
without  the  help  of  glasses  (page  55). 


LESSON  XXV. 
DISEASES  OF  THE  RETINA. 

HYPEREMIA    AND    ANEMIA. 

The  retinal  vessels  do  not  participate  much  in  the 
changes  of  the  intra-cranial  circulation.  There  is 
some  retinal  congestion  in  meningitis  and  always 
venous  engorgement  in  papillitis  and  thrombosis  of  a 
retinal  vein.  The  same  condition  of  the  veins,  in 
milder  form,  is  often  met  with  in  emphysema  and  in 
weakness  of  the  heart's  action.  Slight  hyperemia  of  the 
retina  and  disc  are  sometimes  associated  with  the  strain 
of  an  uncorrected  refractive  error,  but  these  mild  hypere- 
mias are  difficult  of  diagnosis  owing  to  the  variations 
in  the  appearance  of  the  fundus,  found  in  health. 

Anemia  of  the  retina  may  result  from  embolism  of 
the  central  artery,  great  loss  of  blood,  cholera,  spasm  of 
the  arterial  coats  due  to  toxic  doses  of  quinin  and  from 
spasm  due  to  vaso-motor  disturbance.  The  dimness 
of  vision  found  in  some  cases  of  migraine  or  "blind 
headaches"  are  examples  of  the  latter  condition. 

RETINAL  CHANGE  FROM  DIRECT  SUN  RAYS;  SNOW  BLIND- 
NESS;   ELECTRIC    OPHTHALMIA. 

Persons  who  have  looked  directly  at  the  sun  have 

sometimes  complained  afterward   of  central  scotoma. 

These  blind  spots  vary  in  their  severity  and  persistency, 

sometimes  being  ])ermanent.     There  may  be  central 

191 


192  LESSONS    ON    THE    EYE. 

defect  for  colors  and  also  metamorphopsia.  The 
ophthalmoscope  will  often  show  a  minute  lesion  near 
the  macula.  The  treatment  consists  of  rest  of  eyes, 
dark  glasses,  and  hypodermatic  injections  of  strychnin. 

As  a  rule,  the  only  result,  if  any,  of  exposing  the  eyes 
to  the  glare  of  the  snow  is  a  mild  form  of  conjunctivitis, 
but  sometimes  there  is  temporary,  and,  in  rare  in- 
stances, permanent  amblyopia. 

Exposure  of  the  eyes  to  strong  electric  light,  as  in 
electric  welding,  may  result  in  severe  changes,  such  as 
are  found  in  injury  by  direct  sunlight,  and  may  take  a 
mild  form  of  ophthalmia,  such  as  is  occasioned  by 
exposure  to  snow.  Electric  workers  now^  prevent 
these  conditions  by  using  glasses  deeply  colored  with 
yellow,  ruby,  or  a  combination  of  deep  blue  and  red. 

EMBOLISM    AND    THROMBOSLS    OF    RETINAL 
VESSELS. 

Syniptoiiis  of  Eiubolisni. — Sudden  loss  of  vision,  par- 
tial if  the  obstruction  lodges  in  a  branch  artery,  total 
if  it  stops  in  the  main  trunk.  The  blood  vessels  will 
be  much  reduced  in  size.  The  retina  will  be  white  and 
opaque,  the  greatest  opacity  lying  in  the  region  around 
the  macula  and  disc.  The  macula  will  appear  as  a 
cherry-red  spot,  owing  to  the  fact  that  it  is  much  thinner 
than  the  rest  of  the  retina,  and  the  choroid  shows 
through  it.  Degeneration  of  the  retina  occurs  in  a  few 
days,  soon  followed  by  atrophy.  The  optic  nerx'c  gene- 
rally atrophies.     Vision  is  rarely  restored. 

Cause. — The  plug  may  come  from  vegetations  in  the 
heart,  due  to  valvular  disease  or  endocarditis.      It  may 


DISEASES  OF  THE  RETINA. 


193 


also  result  from  aneurism  of  the  aorta  or  from  atheroma 
of  the  arteries.  It  also  occurs  with  Bright's  disease  and 
pregnancy. 

Symptoms  of  Tromhosis. — The  extent  of  visual  loss 
depends  upon  the  location  of  the  thrombus,  in  the  cen- 
tral vein  or  one  of  its  branches.     Vision  is,  as  a  rule. 


Fig.  124, — Embolism  of  the  central  artery  of  the  retina.     (Jennings.) 


not  lost  as  suddenly  as  in  embolism.  There  will  be 
edema  of  the  disc,  tortuosity  and  engorgement  of  the 
veins,  and  numerous  hemorrhages  in  the  area  drained 
by  the  thrombotic  vein.  Cases  do  not  always  present 
the  definite  appearance  here  described.  The  arterial 
circulation  may  be  obstructed  by  endarteritis  and  throm- 
bosis. Closure  of  one  set  of  retinal  vessels  will  produce 
disturbance  in  the  other,  so  that  the  clinical  picture 
made  be  a  composite  of  the  two  conditions. 

Cause. — Retarded  venous  circulation  of  the  old,  the 


194 


LESSONS    ON    THE    EYE. 


emphysematous  or  those  suffering  from  cardiac  lesions. 
It  may  also  be  due  to  phlebitis. 

Treatment  of  embohsm  and  thrombosis  is  of  little 
avail.  An  attempt  may  be  made  to  absorb  the  ob- 
struction by  using  iodid  of  potassium.  Digital  massage 
of  the  ball  has  been  recommended  for  recent  embolism. 


Fig.  125. — Thrombosis  of  the  retinal  veins.     (Jennings.) 


RETINITIS. 

Inflammation  of  the  retina  may  be  limited  to  this 
membrane  or  may  be  associated  with  inflammation  of 
the  optic  nerve  (neuro-retinitis)  or  choroid  (choroido- 
retinitis).  The  disc  is  usually  involved  unless  the 
retinitis  is  ^'ery  mild,  and  some  opacity  of  the  vitreous 
often  co-exists.  Owing  to  the  fact  that  the  disease  is 
generally  constitutional  in  origin,  we  find  it  almost 
always  bilateral.     Normally  the  retina  is  a  transparent 


DISEASES    OF    THE    RETINA.  1 95 

membrane,  but  when  inflamed  it  appears  smoky  or 
hazy  and,  at  times,  to  such  an  extent  as  to  obscure  its 
vessels  in  some  part  of  their  course.  The  veins  may 
appear  unusually  large  and  tortuous  and  frequently 
there  are  hemorrhages.  Often  there  will  appear  dis- 
tinct white  spots  arranged  along  the  course  of  the  ves- 


(Mcycr.) 


sels  or  around  the  macula  or  disc.  These  spots  can 
be  differentiated  from  choroidal  atrophy  by  the  absence 
of  the  pigmented  border  and  the  softness  of  their  out- 
line. In  retinitis  there  will  be  dimness  of  vision  in  all 
degrees.  There  may  be  limitation  of  the  field  of  vision 
and  perhaps  scotomata.  Micropsia  (objects  appearing 
unnaturally  small),  megalopsia  (objects  unnaturally 
large),  metamorphopsia  (unnatural  position  of  objects 


[96 


LESSONS    ON   THE   EYE. 


in  the  field,  straight  Hnes  appearing  wavy,  etc.)  and 
night  blindness  are  forms  of  visual  disturbance  which 
may  be  manifested.  There  may  be  photophobia,  but 
there  will  be  no  pain  and  no  external  evidence  of  inflam- 
mation. Recovery  may  take  place  with  little  or  no 
loss  of  vision,  but  generally  the  prognosis  is  grave.  The 
result  depends  largely  upon  the  cause  of  the  attack 
and  the  region  of  the  retina  involved.     Different  forms 


Fig.  127. — Recent  severe  retinitis  in  renal  disease.     (Govvers.) 


of  the  disease  are  named  according  to  etiology,  leu- 
kemic, albuminuric,  diabetic,  gouty,  and  syphihtic. 
There  are  other  forms  named  from  characteristic  fea- 
tures, such  as  simple,  hemorrhagic,  and  purulent  retinitis. 
Many  forms  of  retinitis  have  been  described  as  distinct 
pathologic  conditions,  w^hen  they  are  probably  varying 
pictures  of  an  identical  pathologic  process.  The 
purpose  of  this  book  restricts  it  to  a  general  descrip- 


DISEASES    OF    THE    RETINA.  1 97 

tion  of  retinitis  and  a  differentiation  of  its  commoner 
types. 

Albuminuric  retinitis  occurs  in  about  7  per  cent, 
of  all  forms  of  albuminuria.  It  appears  late  in  the 
stage  of  the  renal  trouble,  the  majority  of  patients 
dying  within  two  years  after  its  advent.  Both  eyes 
are  generally  affected.  The  characteristic  feature  is 
the  presence  of  the  white  spots  of  fatty  degeneration 


Fig.  128. — -Renal  retinitis  at  a  late  stage.     (Wecker  and  Jaeger.) 

which  tend  to  arrange  themselves  in  a  stellate  figure 
around  the  macula.  Complete  recovery  from  albumin- 
uric retinitis  has  been  observed. 

Diabetic  retinitis  presents  the  same  general  sympto- 
matic picture  as  albuminuric  retinitis.  If  there  is  any 
difference  it  is  that  the  white  degenerated  spots  are 
more  diffuse  and  have  not  the  same  tendency  to  a  stel- 


190  LESSONS    ON   THE   EYE. 

late  formation  around  the  macula  in  diabetic  retinitis. 
Hemorrhages  are  also  more  numerous  in  the  latter  form. 
Often  the  differentiation  will  depend  upon  the  urinary 
analysis. 

Syphilitic  retinitis  occurs  from  congenital  as  well  as 
acquired  syphilis.  It  is,  as  a  rule,  associated  with 
choroiditis  and  opacity  of  the  vitreous.  Night  blind- 
ness is  a  prominent  symptom.  The  general  characteris- 
tics are  those  already  described.  If  the  white  spots  of 
fatty  degeneration  are  present  they  are  numerous,  very 
small  and  scattered  rather  than  arranged  around  the 
macula.  The  latter  arrangement  being  almost  pathog- 
nomonic of  renal  disease.  See  Syphilitic  Choroido- 
retinitis,  page  168. 

Hemorrhagic  retinitis,  as  the  name  implies,  is  an 
inflammation  of  that  tissue  in  which  hemorrhages 
are  the  most  prominent  feature.  These  flame-like 
extravasations  may  be  scattered  over  the  whole  fundus. 
The  optic  disc  is  usually  edematous,  the  veins  tortuous 
and  enlarged.  Vision  depends  largely  upon  the  loca- 
tion of  the  hemorrhagic  spots  in  relation  to  the  macula. 
The  disease  appears  after  middle  life  and  in  those  suffer- 
ing from  disease  of  the  heart  or  of  the  vessel  walls. 
The  ophthalmoscopic  picture  is  practically  identical 
with  that  of  thrombosis  of  the  retinal  vein  and  dif- 
ferentiation may  be  impossible. 

Cause. — Generally  one  of  the  constitutional  condi- 
tions enumerated  above  is  responsible  for  the  disease. 
The  etiology  of  simple  idiopathic  retinitis  is  obscure. 

Treatment. — Demand  absolute  rest  of  the  eyes. 
Subdue  the  light  by  the  use  of  smoked  glasses.  Treat 
the  constitution  as  indicated  by  each  case. 


DISEASES    OF    THE    RETINA. 


199 


RETINITIS    PIGMENTOSA. 

This  is  a  degenerative  rather  than  an  inflammatory 
condition.  It  is  extremely  chronic  in  its  course,  some 
times  requiring  years  to  reach  its  usual  termination  in 
blindness.  Vision  is  much  affected,  but  the  symptom 
most  complained  of  is  night  blindness.  The  field  of 
vision  gradually  contracts  until  only  central  vision  is 


Fig.  129. — Pigmentary  degeneration  of  the  retina.     (Jaeger.) 

left.  This  much  may  remain  for  years.  The  fundus 
shows  a  peculiar  stellate  pigmentation  beginning  at  its 
periphery  and  extending  gradually  to  the  macula. 
The  amount  of  pigment  is  no  measure  of  the  gravity 
of  the  case.  The  caUber  of  the  retinal  vessels  dimin- 
ishes and  there  is  slow  atrophy  of  the  retina  and  disc, 
with  occasional  opacity  of  the  posterior  lens  capsule. 
The  -cause  is  obscure,  but  consanguinity  of  parents 
seems  to  be  an  etiological  factor.     No  treatment  is 


LESSONS    ON   THE    EYE. 


successful.     Galvanism,  subconjunctival  injections  of 
salt  solution  and  strychnin  have  been  recommended. 

DETACHMENT    OF    THE    RETINA. 

This  condition  consists  in  a  separation  of  the  retina 
from  the  choroid,  the  intervening  space  being  occupied 


Fig.  130. — Ophthalmoscopic  appearance  of  detached  retina  (erect  image). 
(After  Wecker  and  Jaeger.) 

by  a  serous  fluid,  blood,  or  a  tumor.  Vision  is  affected 
in  proportion  to  the  extent  and  location  of  the  detach- 
ment, the  field  showing  a  defect  corresponding  to  the 
position  of  the  lesion.     The  ophthalmoscope  reveals  a 


Fig. 


il  detachment  of  retina.     (Nettleship.) 


[31. — Section  of  eye  with  parti 

steel-gray  reflex  from  the  detached  part,  over  which 
the  retinal  vessels  flow.  The  presence  of  the  vessels 
distinguishes  this  from  any  other  condition  presenting  a 
similar  reflex.  If  the  detachment  be  recent  there  will 
be  partial  loss  of  vision,  which  increases  with  the  degen- 


DISEASES  OF  THE  RETINA.  20I 

eration  of  the  retina.  The  retina  rarely  returns  to  its 
normal  condition.  The  size  of  the  detachment  may  re- 
main stationary  or  may  extend  over  the  entire  fundus. 
Cause. — Blows  upon  the  ball  or  jars  by  transmitted 
force.  Tumors  of  the  choroid.  Disease  resulting  in 
fluidity  or  shrinkage  of  the  vitreous.  High  degrees  of 
myopia. 


Treatment. — Long-continued  rest  in  bed  with  eye 
bandaged.  Evacuation  of  the  subretinal  fluid  by  a 
knife,  needle,  or  pointed  cautery ;  or  absorption  of  it  by 
pilocarpine  sweats  and  abstinence  from  fluids.  Sub- 
conjunctival injections  of  salt  solution.  The  results 
of  treatment  are  discouraging. 

GLIOMA    OF    THE    RETINA. 

This  very  malignant  tumor  is  either  congenital  or 
appears  in  childhood.     The  first  symptom  noticed  is  a 


202  LESSONS    ON    THE    EYE. 

yellow  reflex  from  the  pupil.  Tests  will  prove  the  eye 
to  be  blind.  It  is  difficult  to  differentiate  from  pseudo- 
glioma  in  this  stage  (page  171).  Owing  to  the  great 
rapidity  of  the  tumor's  growth  the  diagnosis  can  soon 
be  made.  Active  inflammation,  increased  tension,  and 
pain  soon  develop  with  glioma;  whereas  in  pseudo- 
glioma  there  is  no  pain  and  the  tendency  is  toward 
diminished  tension  and  shrinkage  of  the  ball.  In  a  few 
months  the  tumor  fills  the  eyeball  and  with  its  con- 
tinued growth  protrudes  between  the  lids,  fills  the  orbit, 
and  extends  to  the  brain.  Distant  organs  may  become 
affected.  If  the  eyeball  is  removed  when  the  tumor  is 
confined  within  it,  there  is  some  hope  for  the  patient. 
When  in  doubt  as  to  the  diagnosis,  enucleate,  as  no 
harm  is  done  if  the  case  proves  to  be  pseudo-glioma. 


LESSON  XXVI. 

DISEASES  OF  THE  OPTIC  NERVE. 

Optic  neuritis,  or  inflammation  of  the  optic  nerve, 
may  be  divided  into  two  kinds :— . 

1.  Papillitis,  which  involves  the  intra-ocular  end  of 
the  nerve. 

2.  Retro-bulbar   neuritis,    which    affects    the    nerve 
between  the  ball  and  the  chiasm. 

PAPILLITIS. 

The  optic  disc  or  papilla  is  the  intra-ocular  termina- 
tion of  the  nerve  or  that  part  between  the  lamina  cri- 
brosa  and  the  retina.  With  the  opthalmoscope  the  nor- 
mal disc  appears  as  a  white,  circular  area  in  the  orange 
colored  groundwork  of  the  choroid.  The  white  reflex 
of  the  disc  is  caused  by  the  lamina  cribrosa  showing 
through  the  transparent  nerve  fibers.  In  inflamma- 
tion of  the  disc  there  are  no  definite  subjective  signs. 
There  is  usually  contraction  of  the  field  of  vision  and 
derangement  of  color  perception,  but  vision  may  not 
be  reduced  until  late  in  the  progress  of  the  disease. 
Main  rehance  in  diagnosis  is  placed  on  the  ophthalmo- 
scope, which  shows  a  serous  infiltration  of  the  disc 
manifested  by  redness,  sweUing,  and  loss  of  its  outline. 
The  retinal  arteries  appear  small  and  the  veins  filled 
and  tortuous.  The  strangulation  of  the  veins  some- 
times results  in  hemorrhages  in  the  retina.  In  the 
203 


204  LESSONS    ON    THE    EYE. 

great  majority  of  cases  both  nerves  are  inflamed.  If 
the  inflammation  extend  by  continuity  of  tissue  to  the 
retina,  the  condition  is  called  neuro-retinitis.  Papillitis 
may  sometimes  result  in  complete  recovery,  but  in  the 
majority  of  cases  a  partial  or  total  atrophy  of  the  nerve 
results. 

Cause. — If  monolateral  it  is  generally  the  result  of 
some  orbital  lesion.  When  bilateral  it  is  usually  due 
to  intracranial  disease,  most  frequently  to  tumors, 
but  it  may  be  due  to  meningitis,  abscess,  depressed 
fracture  or  softening.  It  may  also  be  the  result  of 
albuminuria,  diabetes,  syphilis,  lead  poison,  and  anemia. 
The  prognosis  will  depend  largely  upon  the  etiology. 

Treatment. — Forbid  use  of  eyes.  Direct  your  efforts 
to  the  cause,  and  when  in  doubt  give  iodid  of  potassium, 
and  build  up  the  constitution  by  the  usual  methods. 

RETRO-BULBAR    NEURITIS. 

This  condition  is  also  called  central  amblyopia  and 
toxic  amblyopia. 

Symptoms. — Loss  of  acute  vision,  the  patient  com- 
plaining of  a  mist  before  the  eyes.  There  will  be  cen- 
tral scotoma  for  red  and  green,  and  in  advanced  cases, 
central  scotoma  for  objects.  The  affection  is  nearly 
always  bilateral  and  the  vision  of  the  two  eyes 
nearly  the  same  except  in  those  cases  due  to  morbid 
conditions  of  the  nose  which  are  more  frequently 
unilateral.  There  is  no  contraction  of  the  field,  which 
aids  in  the  differentiation  from  progressive  atrophy. 
In  pronounced  cases,  the  disc  shows  an  unnatural 
whiteness  of  its  temporal  side,  and  in  an  advanced 


DISEASES    OF    THE    OPTIC    NERVE. 


205 


state  the  whole  disc  may  present  the  appearance  of 
atrophy.  There  is  proHferation  of  connective  tissue 
in  the  nerve  and  atrophy  of  those  fibers  which  go  to  the 
macula.  The  progress  of  the  disease  is  slow,  and  the 
chance  of  recovery  good  unless  of  too  long  standing. 
It  is  almost  exclusively  a  disease  of  men. 

Cause. — It  is  due,  in  the  great  majority  of  cases,  to 
the  excessive  use  of  tobacco  or  alcohol.     Many  obser- 


g^j^^^jj; 


-r-iii] 


Fig.  133. — Ophthalmoscoj.il  \ii  .\  ..[  ilic  .lisc  in  optic  neuritis.  The  out- 
line of  the  disc  is  clouded.  The  retinal  arteries  are  contracted,  the  retinal 
veins  are  dilated  and  tortuous  and  both  are  hazy  in  places.     (Fuchs.) 


vers  consider  tobacco  the  most  potent  etiological  factor, 
and  some  entirely  acquit  alcohol  of  any  responsibility 
for  the  disease.  Alcoholic  extract  of  Jamaica  ginger, 
essence  of  peppermint,  etc.,  are  very  popular  in  some 
prohibition  regions  and  a  number  of  serious  cases  of 
amblyopia  have  been  reported  from  their  use.  The 
methyl  alcohol  which  they  contain  is  considered  the 
toxic  agent.     Exposure  to  cold,  diabetes,  rheumatism, 


206  LESSONS    ON    THE    EYE. 

syphilis,  and  poison  by  some  chemicals,  among  which 
are  iodoform  and  bisulfid  of  carbon,  are  supposed  to 
be  causative ;  and  there  are  also  some  cases  in  which  no 
cause  can  be  discovered.  Many  cases  have  been  re- 
ported lately  which  locate  the  cause  in  suppuration  of 
the  nasal  sinuses  adjoining  the  orbit.  Whenever  in 
doubt  the  nose  should  be  carefully  explored. 


longitudinal  section      (Fuchs.) 


Treatment. — Absolute  abstinence  from  the  offending 
poison."  When  not  contra-indicated  elimination  of 
the  poison  by  purgatives  or  sweats  is  advisable.  Watch 
the  patient's  digestion  and  give  iodid  of  potassium  or 
strychnin.  When  due  to  a  constitutional  disease, 
treatment  should  be  directed  to  the  cause.  If  due  to 
intra-nasal  disease  the  services  of  a  skilled  rhinologist 
will  be  required. 

QUININ    AMBLYOPIA. 

Overdoses  of  quinin  cause  another'  form  of  toxic 
amblyopia  in  which  the  symptoms  are  so  dift'erent  from 
those  just  enumerated  as  to  merit  a  separate  description. 

Symptoms. — The  general  symptoms  of  cinchonism 
will  precede  the  loss  of  vision.     The  amount  of  visual 


DISEASES    OF    THE    OPTIC    NERVE.  207 

disturbance  varies  from  a  blurring  of  objects  to  absence 
of  light  perception.  The  pupils  may  be  widely  dilated 
and  the  ophthalmoscope  reveal  a  picture  similar  in  some 
respects  to  that  presented  by  embohsm  of  the  central 
artery.  When  there  is  sufficient  vision  to  make  a  test 
possible,  the  field  will  be  found  contracted  and  color 
perception  lost.     After  a  variable  period  vision  is  de- 


FlG. 


-Optic  neuritis  with  hydrops  of  the  optic  nerve  sheaths 
Pagenstecher  and  Genth.) 


(Afler 


cidedly  improved  though  it  rarely  returns  entirely  to 
the  normal.  Salicylate  of  sodium  and  acetanilid  can 
also  produce  a  similar  amblyopia. 

Cause. — The  action  of  the  drug  on  the  vaso-motor 
centers  is  supposed  to  be  such  as  to  cause  a  violent  con- 
striction of  the  blood  vessels.  An  anemia  of  the  retina 
is  the  result. 

Treatment. — Use  of  the  offending  drug  should  be  dis- 
continued at  once.  Inhalations  of  nitrite  of  amyl  may 
be  tried.  Strychnin  should  be  given  until  constitutional 
effect  is  felt.  Absolute  rest  of  the  eyes  must  be  enforced 
and  general  health  promoted  in  every  way. 


208 


LESSONS    ON    THE   EYE. 


ATROPHY  OF  THE  OPTIC  NERVE. 

In  atrophy  the  medullary  part  of  the  fibers  is  dis- 
placed by  granular  fat  and  connective  tissue,  with  thick- 
ening of  the  walls  of  the  vessels  and  narrowing  of  their 
calibre. 

Symptoms. — There  is  no  pain  and  no  change  in  the 
appearance  of  the  ball,  unless  total  blindness  exists, 


36. — Atropic  excavation  of  the  disc. 


when  the  pupils  will  be  dilated.  Great  variety  is  mani- 
fested in  the  visual  defects.  The  loss  of  vision  may  be 
rapid  but  is  generally  very  gradual  and  slow.  Central 
vision  is  lowered  and  the  field  contracted,  sometimes  con- 
centrically, sometimes  irregularly.  Color  sense  becomes 
defective  or  lost,  perception  of  green,  red,  and  blue  usu- 
ally disappearing  in  the  order  named.  If  the  atrophy 
be  associated  with  spinal  cord  lesions  we  shall,  as  a  rule, 
find  the  Argyll-Robertson  pupil.  The  disc  will  appear 
abnormally  white  or  gray,  slight  excavation  due  to 


DISEASES    OF   THE    OPTIC   NERVE.  209 

shrinkage  of  its  substance  may  be  noticed  and  the 
retinal  vessels  will  be  reduced  in  size. 

Cause. — Spinal  diseases  of  which  tabes  dorsalis  is  the 
most  important,  papillitis,  pressure  of  tumors,  disease 
of  the  orbit,  suppuration  in  the  nasal  sinuses,  throm- 
bosis and  embolism  of  the  retinal  vessels,  glaucoma, 
meningitis,  syphiHs,  alcoholism,  and  anemia  from  great 
loss  of  blood  may  cause  atrophy  of  the  optic  nerve.  It 
may  appear  as  a  purely  local  disease  independent  of  any 
other  lesion. 

Treatment. — Correct  any  derangement  of  general 
function.  Attack  vigorously  any  suppuration  in  the 
accessory  nasal  sinuses.  The  galvanic  current,  one 
pole  over  the  eye  and  the  other  at  the  back  of  the  neck, 
is  of  doubtful  utility.  Give  iodid  of  potassium,  mercury 
or  strychnin  to  the  point  of  tolerance.  Strychnin  is 
more  efficacious  when  given  hypodermatically.  Anti- 
pyrin,  seven  and  a  half  grains  every  other  day,  hypoder- 
matically is  also  recommended.  Treatment  is  usually 
ineffectual. 


LESSON  XXVII. 

FUNCTIONAL  DISORDERS  OF  VISION,  ETC. 

AMBLYOPIA  AND  AMAUROSIS. 

These  are  terms  used  to  express  a  diminution  or  loss 
of  vision  without  any  apparent  lesion.  The  two  words 
are  used,  more  or  less  indiscriminately,  but  amaurosis 
is  generally  applied  to  the  graver  conditions.  There 
are  many  forms  of  lowered  vision,  the  pathology  of 
which  is  known,  but  they  do  not  come  under  this  head. 
The  cause  of  functional  amblyopia  may  be  known,  but 
the  exact  way  in  which  the  loss  of  vision  is  produced  is 
unexplained. 

1.  Traumatism  to  the  head,  direct  or  indirect,  or  a 
blow  upon  the  eye,  may  be  followed  by  amblyopia, 
more  or  less  persistent.  In  these  cases  it  is  presumed 
that  there  is  some  invisible  lesion  of  the  parts  concerned 
in  vision. 

2.  Loss  of  blood  may  produce  amblyopia,  which 
probably  is  due  to  the  fact  that  the  retina  is  affected  by 
the  general  lack  of  nutrition.  But  we  do  not  know  why 
the  degree  of  amblyopia  is  not  always  commensurate 
with  the  amount  of  blood  lost  or  why  there  is  greater 
tendency  to  amblyopia  from  hemorrhages  of  the 
stomach,  uterus,  and  bowels  than  from  traumatic 
hemorrhages. 

3.  Congenital  amblyopia  generally  affects  but  one 
eye.     It  has  been  mentioned  as  a  factor  in  the  produc- 

210 


FUNCTIONAL   DISORDERS    OF    VISION,    ETC.  211 

tion  of  comitant  strabismus.  It  is  supposed  to  be 
due  to  an  arrest  of  development  of  the  eye  in  fetal 
or  early  infant  life.  Lowered  visual  acuity  is  often 
associated  with  pronounced  errors  of  refraction,  espe- 
cially astigmatism.  If  accurately  corrected  at  an  early 
age  the  eye  may  gradually  develop  normal  acuteness  of 
vision. 

4.  Hysterical  amblyopia  may  occur  in  both  sexes  but 
is  most  frcciucnt  in  females.  As  might  be  supposed  the 
symptoms  assume  a  great  variety  of  forms,  such  as  total 
blindness,  hemianopsia,  scotoma,  color  blindness,  and 
contraction  of  the  visual  field.  Neurasthenic  school 
children,  especially  girls,  are  frequently  thus  afflicted 
and  great  tact  and  judgment  are  required  in  their 
treatment. 

5.  Simulated  amblyopia,  or  malingering,  may  be  due 
to  a  desire  to  exaggerate  an  injury  over  which  a  lawsuit 
is  pending,  to  secure  a  pension,  to  escape  some  disagree- 
able duty  or  to  excite  sympathy.  For  obvious  reasons, 
but  one  eye  is  claimed  to  be  affected.  Numerous  tests 
will  reveal  the  patient's  hypocrisy,  if  he  claims  blindness 
in  but  one  eye,  among  which  are  the  following : — 

1.  Put  on  him  a  pair  of  spectacles,  one  lens  of  which 
is  plain  glass  and  the  other  a  prism  with  its  base  up  or 
down.  If  malingering  he  will  see  double  and  an  effort 
to  walk,  especially  to  go  down  stairs,  will  be  made  so 
cautiously  that  his  true  condition  is  detected. 

2.  Place  before  the  eye  he  claims  is  bad  a  plain  glass 
and  before  the  other  a  plus  glass  just  strong  enough  to 
obscure  its  vision.  If  with  these  vision  is  normal,  the 
patient  is  malingering. 

3.  Hang  some  green  letters  in  front  of  a  black  back- 


212  LESSONS    ON   THE   EYE. 

ground,  at  a  convenient  distance.  Hold  before  the 
good  eye  a  glass  colored  red.  If  he  reads  the  letters,  he 
does  it  with  his  bad  eye,  as  the  green  letters  cannot  be 
seen  through  the  red  glass.  Red  letters  on  a  white 
background  are  much  obscured  when  seen  through  a  red 
glass. 

4.  Put  a  drop  or  two  of  atropin  in  the  good  eye  and 
to  allay  suspicion  an  equal  number  of  drops  of  cocain 
may  be  put  in  the  bad  eye.  When  time  enough  has 
elapsed  for  the  atropin  to  paralyze  accommodation, 
hand  the  patient  a  book.  If  he  reads  it  he  does  so  with 
the  eye  he  claims  to  be  amblyopic. 

If  the  patient  claims  to  be  bUnd  in  both  eyes  his 
detection  is  more  difficult  and  a  close  watch  may  be 
necessary  to  determine  the  true  condition.  A  simple 
test,  which  may  be  of  service,  is  to  ask  the  patient  to 
look  at  his  own  hand.  A  blind  man  will  turn  the  eye- 
balls toward  the  hand,  a  malingerer  may  intentionally 
look  in  some  other  direction. 

AMAUROSIS  PARTIALIS  FUGAX. 

This  condition,  which  is  also  known  as  scintillating 
scotoma  is  a  very  common  form  of  temporary  disturb- 
ance of  vision.  It  may  not  be  recognized  owing  to  the 
unsatisfactory  description  of  his  symptoms  given  by 
the  patient.  A  sudden  blurring  of  the  vision  is  noticed, 
which  for  a  period  of  five  minutes  gradually  gets  worse. 
Reading  is  then  almost  impossible  and  distinct  objects 
have  a  veiled  and  confused  outline.  There  is  a  very 
uncomfortable  flickering  or  glimmering  appearance  in 
the  field  of  vision.     The  sensation  is  likened  to  that 


FUNCTIONAL    DISORDERS    OF    VISION,    ETC.  213 

presented  by  the  atmosphere  which  rises  over  a  red  hot 
stove.  There  may  be  flashes  Hke  zig-zag  Hghtning 
circling  around  the  periphery  of  the  field,  and  homony- 
mous hemianopsia  may  be  present.  The  uncomfortable 
sensation  is  not  dispelled  by  closing  the  eyes.  In  about 
thirty  minutes  the  symptoms  disappear  and  are  followed 
in  the  majority  of  cases  by  a  frontal  headache.  The 
attacks  vary  in  frequency  from  one  in  a  life  time  to 
several  a  day.  It  is  supposed  to  be  due  to  a  circulatory 
disturbance  in  the  brain  cortex.  Patients  will  attribute 
it  to  an  indefinite  variety  of  causes.  Treatment  con- 
sists in  improving  the  general  condition  of  the  patient. 
Validol  in  20-drop  doses  has  been  recommended. 

HEMIANOPSIA. 

Hemianopsia  is  a  term  used  to  express  diminution  or 
total  loss  of  vision  in  one-half  of  the  field.  Both  eyes 
are  usually  affected,  which  indicates  a  lesion  in  or  back 
of  the  chiasm.  If  only  one  eye  is  affected  the  lesion  is 
probably  in  front  of  the  chiasm.  In  the  great  majority 
of  cases  of  hemianopsia  affecting  both  eyes  the  diminu- 
tion or  loss  of  vision  will  be  in  the  right  half  of  each 
field  or  the  left  half  of  each  field.  This  is  called 
homonymous  hemianopsia.  We  may  have  loss  of  the 
external  half  of  each  field  called  bitemporal  hemianop- 
sia, or  of  the  internal  half  of  each  field  called  binasal 
hemianopsia,  but  these  conditions  are  rare.  A  condi- 
tion still  more  uncommon  is  loss  of  the  upper  or-  lower 
field.  The  lesion  which  causes  hemianopsia  may  lie  at 
any  part  of  the  visual  tract  from  the  eyeball  to  the  cor- 
tex of  the  brain  and  a  knowledge  of  the  origin  and  dis- 


214 


LESSONS    ON    THE    EYE. 


tribution  of  the  optic  nerve  fibers  is  necessary  to 
determine  its  location.  The  lesion  may  be  a  tumor, 
periostitis,  blood  clot,  softening  of  the  brain,  atheroma 
of  adjacent  vessels,  injuries,  etc.  Treatment  must  be 
directed  to  the  cause. 


Fig.  137. — Lesion  at  A,  A,  would  cause  right  hf)monymous  hemianopsia. 
B,  B,  would  cause  left  homonymous  hemianopsia.  C,  C,  would  cause  bitem- 
poral hemianopsia.     D,  D,  would  cause  binasal  hemianopsia. 


NIGHT  BLINDNESS. 

Most  authors  use  the  word  hemeralopia  to  express 
night  blindness  and  nyctalopia  to  express  day  blindness. 
Greenhill  has  proven  that  they  are  in  error  and  that  the 
reverse  is  correct  according  to  derivation  and  ancient 
usage.  The  night  blindness  of  retinitis  pigmentosa 
must  not  be  confounded  with  the  functional  variety 
being  described  in  which  there  are  no  visible  lesions  of 
the  fundus.  In  functional  night  blindness  vision  may 
be  normal  in  a  bright  light  but  is  greatly  lowered  on  dull 
days,  in  the  twilight  or  in  dimly  lighted  rooms.     It  is 


FUNCTIONAL    DISORDERS    OF    VISION,    ETC. 


215 


found  in  persons  who  have  been  exposed  to  glaring 
Hght,  such  as  travelers  in  the  tropics,  glass  blowers, 
electric  welders  and  those  who  work  before  furnaces. 
It  is  also  supposed  to  be  associated  with  certain  states 
of  lowered  vitality  such  as  scorbutus,  starvation,  etc. 
The  treatment  consists  in  protection  of  the  eyes  by 
dark  glasses,  the  use  of  tonics  of  quinin,  iron,  strychnin 


Fig.  138. — The  right  and  left  field  of  vision  in  homonymous  hemianopsia, 
resulting  from  unilateral  cerebral  hemorrhage.  The  darkened  areas  indicate 
the  obliterations.     The  normal  areas  remaining  are  contracted. 

and  cod  Hver  oil,  and  changing  the  occupation  if  that 
seems  at  fault.  Mallannah  says  decreased  alkalinity 
of  the  blood  is  the  cause  of  night  blindness  and  recom- 
mends the  use  of  urotropin. 


DAY  BLINDNESS. 

This  condition  is  the  opposite  to  night  blindness  in 
that  the  patient  sees  better  and  greatly  prefers  dimin- 
ished illumination.  It  is  found  as  a  symptom  in  retro- 
bulbar neuritis,  albinism,  dilation  of  the  pupil  from 
third  nerve  paralysis  or  from  the  use  of  a  mydriatic,  cen- 
tral cataract,  etc.  It  also  exists  as  a  functional  con- 
dition independent  of  any  demonstrable  lesion.     Func- 


2l6  LESSONS    ON    THE    EYE. 

tional  day  blindness  is  found  in  persons  who  have  been 
excluded  from  the  light  for  a  long  period  and  is  also  a 
frequent  symptom  of  hysteria. 

When  day  blindness  is  a  symptom,  the  primary  affec- 
tion should  be  treated.  If  it  is  functional  examine 
closely  for  muscular  insufficiency  and  errors  of  refrac- 
tion ;  build  up  the  constitution  and  accustom  the  eyes 
to  light  by  resorting  to  the  strategy  demanded  by  each 
case. 


LESSON  XXVIII. 

GENERAL  THERAPEUTICS. 

THE  APPLICATION  OF  HEAT  AND  COLD. 

Heat  is  of  great  service  in  relieving  pain  in  and  around 
the  eye.  Dry  heat  is  best  apphed  by  means  of  a  Japa- 
nese box.  This  is  a  small  tin  case  which  can  be  kept 
hot  for  several  hours  by  means  of  a  burning  cartridge 
of  punk.  Flannel  cloths,  heated  before  a  fire  or  in  an 
oven,  are  efficacious,  but  require  frequent  changing. 

Moist  heat  is  secured  by  cloths  wrung  out  of  very  hot 
water.  They  should  be  changed  often  enough  to  main- 
tain an  equable  temperature.  Another  w^ay  of  applying 
moist  heat  is  to  fill  a  tumbler  to  the  brim  with  hot  water 
and  then  place  the  eye,  with  the  lids  closed,  as  far  in  it 
as  possible.  Moist  heat  by  stimulating  the  circiilation 
promotes  resolution,  as,  for  example,  in  ulceration  of 
the  cornea.  It  hastens  the  suppurative  process  as  in 
phlegmon  of  the  lid.  It  is  applicable  to  all  deep-seated 
inflammations,  such  as  iritis  and  glaucoma.  Heat  is 
usually  applied  for  fifteen  to  thirty  minutes  at  a  time, 
three  or  four  times  a  day. 

Cold  is  of  service  in  restraining  the  inflammatory  proc- 
ess after  traumatisms  and  in  reducing  the  congestion 
of  conjunctival  inflammations.  Muslin  squares  may 
be  placed  on  a  block  of  ice  and  transferred  to  the  eye 
with  sufficient  frequency  to  maintain  the  desired  tem- 
perature. The  desired  effect  may  also  be  secured  by 
217 


2l8  LESSONS    ON    THE    EYE. 

wringing  the  cloths  out  of  cold  water  and  changing 
them  frequently.  The  cold  application  on  page  io6  is 
very  grateful. 

ANESTHETICS. 

General  anesthesia  should  be  used  on  unruly  patients, 
in  plastic  operations,  enucleations,  advancements  of 
the  muscles  and  w^hen  there  is  so  much  inflammation 
that  local  anesthetics  are  ineffective. 

Local  anesthesia  will  suffice  for  the  majority  of  eye 
operations.  The  removal  of  chalazions  and  other  lid 
operations  are  not  rendered  painless  by  the  instillation 
of  a  local  anesthetic.  It  must  be  injected  into  the 
tissues  and  this  is  often  impracticable  ow4ng  to  the 
change  produced  in  the  relationship  of  the  parts. 

Cocain  hydrochlorate  is  used  in  two  to  four  per  cent, 
solutions.  If  greater  strength  is  needed  its  toxic  prop- 
erties must  not  be  forgotten.  The  indiscriminate  use  of 
cocain  in  the  treatment  of  eye  diseases  is  to  be  deplored. 
It  is  questionable  if  it  serves  a  good  purpose  in  any 
other  role  except  that  of  an  anesthetic.  There  is  no 
doubt  of  its  ability  to  do  harm  under  certain  conditions. 
It  causes  a  drying  out  and  exfoliation  of  the  epithelial 
layer  of  the  cornea.  To  prevent  this  the  patient  may 
keep  the  lids  closed  between  instillations"  and  in  opera- 
tions some  bland  aseptic  solution  may  be  dropped  on 
the  cornea  at  proper  intervals.  Cocain  also  reduces  the 
intra-ocular  tension,  constricts  the  small  blood  \'essels 
and  dilates  the  pupil .  For  the  removal  of  foreign  bodies 
from  the  cornea,  one  drop  is  often  all  that  is  necessary. 
A  second  drop  a  minute  later  will  quite  suffice.  For  the 
formidable  operations  more  instillations  are  required. 


GENERAL    THERAPEUTICS.  219 

Cocain  spoils  quickly  and  old  solutions  should  not  be 
used. 

Holocain  hydrochlorate  is  used  in  a  one  per  cent, 
solution.  It  causes  slight  pain  when  first  dropped  in 
the  eye.  It  does  not  reduce  congestion  or  lessen  hemor- 
rhage by  constricting  the  blood  vessels  as  does  cocain. 
Its  advantages  over  cocain  are  that  it  does  not  dilate  the 
pupil,  causes  no  drying  of  the  cornea,  will  not  spoil  in 
solution,  and  has  some  antiseptic  properties.  Holocain 
should  not  be  used  hypodermatically.  The  bottle 
should  be  washed  out  with  pure  muriatic  acid  before 
a  solution  of  holocain  is  put  in  it,  otherwise  a  combina- 
tion with  the  trace  of  lead,  always  found  in  a  new  bottle, 
will  take  place. 

Eucain  "B"  has  proven  too  irritating  to  supplant 
either  of  the  above  anesthetics  in  eye  practice. 

Chloretone,  anesin,  acoin,  stovaine,  alypin,  and 
novocain  are  new  local  anesthetics  which  possess  no 
properties  which  especially  recommend  them. 

MYDRIATICS. 

Mydriatics  are  drugs  which  dilate  the  pupil. 

Cocain  hydrochlorate  may  be  used  when  a  temporary 
dilation  is  required  as,  for  example,  for  ophthalmo- 
scopic examinations.  The  eye  must  be  kept  closed  while 
the  pupil  is  dilating  and  too  much  cocain  must  not  be 
used  or  a  wrinkling  of  the  epithelial  layer  of  the  cornea 
w411  prevent  the  examination.  Cocain  does  not  cause 
paralysis  of  the  ciliary  muscle,  consequently  vision  is 
very  slightly  affected  by  its  use.  The  pupil  will  return 
to  its  normal  state  in  an  hour  or  two. 


220  LESSONS    ON   THE   EYE. 

Euphthalmin  hydrochlorate  is  very  similar  in  its  my- 
driatic action  to  cocain .  It  does  not  dry  out  the  corneal 
epithelium  or  paralyze  the  ciliary  muscle.  ■  Euphthal- 
min is  used  in  a  five  per  cent,  solution. 

Ephedrin  hydrochlorate  is  recommended  as  a  useful 
mydriatic  which  will  dilate  the  pupil  without  causing 
paralysis  of  accommodation.  It  is  used  in  a  five  per 
cent,  solution. 

MYDRIATICS  AND  CYCLOPLEGICS. 

A  cycloplegic  is  a  drug  which  causes  paralysis  of  the 
ciliary  muscle  and  resulting  suspension  of  accommo- 
dation.    All  of  the  cycloplegics  are  also  mydriatics. 

Homa tropin  hydrobromate  is  a  satisfactory  mydriatic. 
Its  effect  upon  the  pupil  is  more  lasting  than  that  of 
cocain  or  euphthalmin.  For  mydriasis  one  grain  to  the 
ounce  is  sufficient.  When  homatropin  is  used  as  a 
cycloplegic,  in  testing  for  refractive  errors,  the  mistake 
is  often  made  of  using  it  too  weak.  The  following  pre- 
scription, freshly  made,  will  produce  total  cycloplegia. 

I^  Homatropin  hydrobromate .  .  .  .gr.  i. 

Aq.  distill OSS. 

SiG. — One  drop  in  each  eye  every  ten 
minutes,  for  one  hour. 

Thirty  minutes  after  the  last  drop  the  patient  is 
ready  to  examine.  The  effect  will  wear  oft'  in  about 
thirty-six  hours. 

Atropin  sulfate  is  the  most  powerful  mydriatic  and 
cycloplegic.  A  one  per  cent,  solution  is  usually  em- 
ployed.   Its  effect  will  not  disappear  for  about  ten  days, 


GENERAL   THERAPEUTICS.  221 

therefore  it  must  not  be  used  thoughtlessly  on  those 
who  need  their  near  vision.  It  is  used  when  total  inac- 
tivity of  the  ciliary  muscle  or  wide  dilation  of  the 
pupil  is  desired.  Atropin  is  the  active  principle  of 
belladonna  and  caution  must  be  observed  in  its  use  as 
some  individuals  manifest  a  pronounced  susceptibility 
to  belladonna  poison. 

Duboisin  sulfate  (gr.  1/4  to  gi.),  hyoscyamin  hydro- 
bromate  (gr.  1/4  to  ^i.),  scopolamin  hydrobromate 
(gr.  1/8  to  5ii.),  and  daturin  sulfate  (gr.  1/8  to  5i.) 
are  cycloplegics  whose  action  and  use  are  about  the 
same  as  atropin.  Their  effect  wears  off  in  from  four  to 
seven  days.  The  use  of  a  mydriatic  has  brought  on 
glaucoma  in  the  manner  described  on  page  179.  For 
this  reason  tension  of  the  eye  should  be  noted  and  great 
caution  observed  before  their  use,  particularly  in  elderly 
people. 

MYOTICS. 

Myotics  contract  the  pupil  and  increase  accommoda- 
tion by  stimulation  of  the  ciliary  muscle. 

Eserin  sulfate  or  salicylate  is  the  most  powerful  of  the 
two  myotics  and  is  used  in  strength  varying  from 
gr.  1/20  to  gr.  ii.to  oi-.  depending  upon  the  object  to  be 
attained.  The  w^eakest  dose  is  used  for  the  purpose  of 
stimulating  accommodation  and  the  strongest  in  glau- 
coma, page  181.  Eserin  solutions  become  pink  when 
kept  for  any  length  of  time ;  this  does  not  indicate  any 
deterioration  in  strength. 

Pilocarpin  hydrochlorate  is  much  weaker  than  eserin 
and  is  used  only  when  feeble  action  is  desired.  Grain  i. 
to  §i.  is  the  strength  generally  used.     It  is  also  used 


222  LESSONS    ON    THE    EYE. 

hypodermatically  to  produce  diaphoresis,  for  example, 
in  detachment  of  the  retina  and  in  choroiditis. 


ANTISEPTICS  AND  DISINFECTANTS. 

It  has  been  demonstrated  that  the  thorough  mechani- 
cal cleansing  of  the  conjunctival  sac  with  sterile  water 
or  normal  salt  solution  is  as  successful  a  method  of 
asepticizing  it  as  the  use  of  the  chemical  antiseptics. 
Antiseptics  cannot  be  used  freely  in  strong  solutions 
ow4ng  to  the  danger  of  irritating  the  conjunctiva  and 
injuring  the  cornea.  The  strength  employed  will 
depend  upon  the  object  to  be  attained.  The  same 
antiseptic  may  be  used  in  a  weak  solution  to  remove 
secretion  from  the  conjunctival  sac,  in  a  concentrated 
form  to  disinfect  a  corneal  ulcer  and  in  an  intermediate 
strength  as  an  application  to  the  palpebral  conjunctiva. 

Formalin,  i  to  6,000  solution,  may  be  used  in  the  con- 
junctival sac.  As  a  disinfectant,  applied  directly  to  a 
corneal  ulcer,  on  a  cotton  applicator,  i  to  100  may  be 
used. 

Trikresol  is  one  of  the  least  irritating  antiseptics.  A 
solution  of  I  to  1,000  makes  a  valuable  menstruum  for 
eye  drops  as  bacteria  will  not  develop  in  it. 

Peroxid  of  hydrogen  is  exceedingly  painful.  It  is 
used  to  disinfect  corneal  ulcers,  but  holocain  anes- 
thesia should  precede  it. 

Bichlorid  of  mercury  should  not  be  stronger  than  i  to 
5,000  if  employed  as  a  wash.  It  sometimes  irritates 
in  this  strength.  When  appHed  to  a  trachomatous  lid 
it  may  be  used  as  strong  as  i  to  500,  but  its  action  must 
be  limited  to  the  part  treated. 


GENERAL   THERAPEUTICS.  223 

Biniodid  of  mercury  is  used  as  a  wash  in  Panas'  solu- 
tion, as  follows : 

Mercuric  iodid gi"-  i/7 

Alcohol 5/i. 

Aq.  destill.  q.  s o/^'^- 

Permanganate  of  potash  solution  is  generally  em- 
ployed in  I  to  2,000  strength. 

Pyoktanin  (blue)  in  i  to  2,000  solution  is  sujjposed  to 
be  an  especially  reliable  antiseptic  in  purulent  condi- 
tions of  the  lacrymal  sac. 

Boric  acid,  gr.  xii.  to  §i.,  is  used  as  a  cleansing  wash 
and  as  a  colly rium.  In  the  latter  case  it  is  generally 
combined  with  other  remedies.  Its  antiseptic  proper- 
ties are  quite  limited. 

Borax,  gr.  iv.  to  §i.,  is  similar  in  its  application  to 
boric  acid. 

Carbolic  acid  is  never  used  as  a  cleansing  wash  or  as  a 
collyrium.  It  is  a  popular  disinfectant  for  corneal 
ulcers.  When  thus  applied  a  local  anesthetic  must  be 
used  and  great  care  observed  to  prevent  the  acid  from 
spreading  beyond  the  edge  of  the  ulcer.  Dip  a  lacry- 
mal probe  in  pure  carbolic  acid  and  let  as  much  run  off 
as  will;  what  remains  may  be  sufficient.  It  is  better 
to  repeat  this  process  a  number  of  times  than  to  apply 
so  much  that  it  runs  over  the  healthy  cornea. 

Tincture  of  iodin  is  used  in  infected  corneal  ulcers  the 
same  as  carbolic  acid. 

Silver  nitrate  is  an  old  and  valuable  disinfectant  and 
astringent.  The  preparations  of  silver  are  probably 
the  most  useful  remedies  we  have  in  the  treatment  of 
eye  diseases.     They  are  used  as  prophylactics,  also  in 


224  LESSONS    ON   THE   EYE. 

conjunctival  inflammations  when  pus  is  present,  in 
disease  of  the  Hd  border,  in  diseases  of  the  lacrymal 
sac,  and  in  ulceration  of  the  cornea.  One  per  cent,  solu- 
tion of  nitrate  of  silver  is  dropped  into  the  eyes  of  in- 
fants to  prevent  ophthalmia  neonatorum.  In  |  to  i 
per  cent,  strength  it  is  applied  to  the  palpebral  con- 
junctiva. To  disinfect  ulcers  of  the  cornea  it  is  used 
in  strong  solution  in  the  same  manner  as  carbolic  acid. 
The  "mitigated  stick"  is  composed  of  silver  nitrate 
and  potassium  nitrate  in  various  proportions. 

Protargol,  a  new  organic  salt  of  silver,  is  used  in  five  to 
twenty  per  cent,  solutions.  It  is  not  as  irritating  as 
silver  nitrate  and  seems  to  be  more  efficient  in  some 
conditions. 

Argentamin,  albargin  and  nargol  are  new  silver  prep- 
arations which  have  their  advocates  but  there  seems  to 
be  no  reason  why  they  should  supplant  protargol. 

Argyrol  (silver  vitelline)  is  a  justly  popular  silver 
product.  It  is  painless  and  non-irritating,  contains 
thirty  per  cent,  of  silver,  does  not  coagulate  albumen 
and  is  said  to  have  greater  penetrating  action  than  any 
of  the  other  silver  preparations.  It  is  used  in  five  to 
fifty  per  cent,  solutions. 

The  actual  cautery  is  a  most  useful  •  disinfectant  of 
corneal  ulcers. 

STIMULANTS    AND    ASTRINGENTS. 

Copper  sulfate  crystal  ("  blue  stone")  is  applied  to  the 
palpebral  conjunctiva  in  trachoma  and  chronic  con- 
junctivitis. The  membrane  should  be  touched  lightly 
or  rubbed  with  the  crystal,  depending  upon  the  effect 


GENERAL   THERAPEUTICS.  225 

desired.  The  surface  of  the  crystal  must  be  abso- 
lutely smooth  to  avoid  scratching  the  conjunctiva. 
It  is  sometimes  employed  in  solution  of  one-half  grain 
to  the  ounce. 

Cuprol  is  an  organic  combination  of  copper  and  nucle- 
inic  acid,  containing  about  six  .per  cent,  of  metaUic  cop- 
per. The  ten  per  cent,  solution  is  generally  used  in 
conjunctival  diseases. 

Alum  is  employed  in  chronic  conjunctivitis  in  the 
crystal  form  or  in  a  solution  containing  from  one-half 
a  grain  to  two  grains  to  the  ounce. 

Tannin  dissolved  in  glycerin  in  the  proportion  of  one 
part  of  tannin  to  eight  of  glycerin  is  sometimes  applied 
to  the  palpebral  conjunctiva  in  trachoma.  It  is  also 
recommended  in  phlyctenular  conjunctivitis. 

Zinc  sulphate  is  used  in  coUyria,  in  strength  varying 
from  one  to  two  grains  to  the  ounce.  It  is  of  special 
value  in  diplo-bacillus  conjunctivitis. 

Zinc  chlorid,  grain  one  to  the  ounce,  is  also  very  use- 
ful in  this  disease. 

Boroglycerid  (U.  S.  P.)  is  applied  to  the  everted  Hd 
in  trachoma  and  chronic  conjunctivitis. 

Camphor  water,  a  weak  stimulent  and  astringent,  is 
used  in  coUyria.  One  part  of  camphor  water  to  three 
of  distilled  water  makes  a  good  menstruum  for  stronger 
astringents. 

POWDERS. 

Powders  must  be  triturated  as  thoroughly  as  possible 
before  being  dusted  upon  the  cornea  or  used  in  an 
ointment  in  the  conjunctival  sac. 
15 


226  LESSONS    ON    THE    EYE. 

Calomel  is  dusted  upon  the  cornea  in  cases  of  corneal 
ulceration,  pannus,  and  phlyctenular  ophthalmia.  It 
should  not  be  used  when  an  eye  is  in  a  state  of  active 
inflammation  or  when  the  patient  is  taking  iodids 
internally,  see  page  135. 

Iodoform  is  used  in  corneal  ulceration.  It  may  be 
applied  as  a  powder  or  in  an  ointment.  It  sometimes 
produces  severe  irritation  if  care  is  not  observed  in  the 
selection  of  the  preparation  used. 

Xeroform  and  nosophen  are  antiseptic  powders 
which  are  recommended  in  the  treatment  of  corneal 
ulceration. 


OINTMENTS. 

Yellow  oxid  of  mercury  is  employed  in  the  form  of  an 
ointment  made  with  vaselin,  cold  cream,  or  lanolin. 
When  it  is  to  be  used  in  the  conjunctival  sac  it  will  mix 
better  with  the  tears  if  albolene  is  incorporated.  The 
ointment  should  be  rubbed  until  not  a  grain  of  mercury 
can  be  seen.  One  per  cent,  is  the  usual  strength,  but 
it  may  be  made  stronger  or  weaker.  It  is  used  in  dis- 
eases of  the  lids,  conjunctiva,  and  cornea  as  described 
under  these  subjects.  It  should  not  be -exposed  to  the 
light. 

Ammoniated  mercury  is  indicated  in  the  same  con- 
ditions and  is  employed  in  the  same  strength  as  the 
yellow  oxid. 

Boric  acid,  one  grain  to  the  dram  of  vaseHn,  is  a 
bland  ointment  which  may  be  used  on  the  border  of 
the  lids  to  prevent  them  from  sticking  together  when 
secretion  is  excessive. 


GENERAL   THERAPEUTICS.  227 

MISCELLANEOUS    REMEDIES. 

Jequirity  is  used  to  establish  an  acute  membranous 
conjunctivitis  in  trachoma  and  pannus.  It  seems  to 
have  a  decidedly  beneficial  influence  in  selected  cases. 
Twenty  grains  of  the  decorticated  beans  are  ground, 
then  put  in  an  ounce  of  cold  water  and  allowed  to  stand 
for  twenty-four  hours.  The  palpebral  conjunctiva  is 
painted  with  this  infusion  and  in  a  few  hours  active 
inflammation  sets  in.  In' a  few  days  the  inflammation 
subsides  and  gradual  improvement  of  the  ]3annus 
follows. 

Jequiritol,  a  preparation  sold  by  Merck,  with  full 
instructions  for  its  use,  is  said  to  be  safer  and  more 
reliable  than  the  infusion  of  jequirity  beans. 

Suprarenal  extract  will  produce  a  thorough  hcmostasis 
of  the  conjunctiva.  Tenotomies,  pterygium  opera- 
tions, etc.,  are  rendered  practically  bloodless  by  its  use. 
Adrenalin  chlorid  and  suprarenalin  are  preparations  of 
the  gland  which  may  be  used  in  strength  varying  from 
1 :  5,000  to  1 :  20,000.  The  value  of  suprarenal  extract 
as  a  therapeutic  agent  is  limited.  It  should  not  be 
used  in  glaucoma. 

Dionin  is  a  morphin  derivative  used  generally  in  a  two 
to  five  per  cent,  solution.  It  causes  pain  when  instilled 
into  the  conjunctival  sac  and  should  be  preceded  by  a 
local  anesthetic.  It  is  a  lymphagogue  and  a  few  min- 
utes after  its  application  a  decided  conjunctival  edema 
appears.  It  is  of  decided  value  in  relieving  the  pain  of 
glaucoma,  iritis,  and  iridocyclitis.  It  is  said  to  in- 
fluence the  absorption  of  the  post-operative  debris  of 
cataract.     In  dionin  we  undoubtedly  have  a  valuable 


228  LESSONS    ON    THE    EYE. 

analgesic.  In  addition  to  its  above  uses  it  has  been  rec- 
ommended for  sub-con  junctival  hemorrhage  hy- 
phema, interstitial  keratitis,  vitreous  opacities,  scleritis, 
episcleritis,  and  ulceration  of  the  cornea. 

Fluorescin  is  used  to  determine  the  area  of  the  cornea 
which  is  denuded  of  its  epithelium  by  ulceration  or 
traumatism.  A  drop  of  the  following  solution  placed 
upon  the  cornea  will  stain  green  all  tissue  not  covered 
by  epithelium. 

Fluorescin       gi".  i. 

Sodii  bicarb gr.  ii. 

Aq.  destill 5  ii- 

Ichthyol,  in  a  25  to  50  per  cent,  solution,  has  been 
used  in  conjunctival  affections.  It  has  been  recom- 
mended for  marginal  blepharitis,  in  a  ten  per  cent, 
ointment.  Ichthalbin  is  proposed  as  a  substitute  for 
ichthyol  as  it  is  free  from  the  disagreeable  odor  of  the 
latter. 

The  Roentgen  ray  has  been  used  with  success  in 
cases  of  epithelioma  and  rodent  ulcers  of  the  lids.  It 
seems  of  definite  value  in  trachoma.  It  is  also  recom- 
mended for  vernal  catarrh  and  episcleritis. 

Radium  has  been  used  in  rodent  ulcers,  trachoma, 
episcleritis,  and  corneal  opacities.  It  is  said  to  have 
analgesic  properties  in  cases  of  painful  uveitis. 

Sub-conjunctival  injections  of  salt  solution  and  solu- 
tions of  mercury  have  been  used  for  corneal  ulceration, 
interstitial  keratitis,  all  forms  of  uveitis,  vitreous  opaci- 
ties, and  detachment  of  the  retina.  One  drop  of  one 
per  cent,  solution  of  acoin  should  be  added  to  the 
injected  fluid  to  diminish  the  pain.     The  amount  of 


GENERAL    THERAPEUTICS.  229 

fluid  advised  varies  from  a  few  drops  to  a  syringeful. 
The  physiologic  salt  solution  is  probably  as  efficacious 
as  the  mercury  solutions,  and  is  not  as  liable  to  pro- 
duce inflammatory  adhesions  of  the  sub-conjunctival 
tissues.  The  sub-conjunctival  injection  of  sterilized  air 
has  been  used  as  a  satisfactory  substitute  for  the  above 
solutions. 

Intra-muscular  injections  of  mercury  seem  to  yield 
better  and  quicker  results  than  the  older  methods. 
They  have  been  used  in  optic  neuritis,  progressive 
optic  atrophy,  uveitis,  sympathetic  ophthalmia,  and 
central  chorio-retinitis  as  well  as  in  the  usual  syphilitic 
manifestations.  One-fifth  of  a  grain  of  hg.  succinimid 
is  the  dose  of  the  most  popular  preparation. 

Serum  therapy  and  vaccine  therapy  are  engaging  the 
attention  of  many  investigators.  Their  value  as 
therapeutic  agents  in  the  treatment  of  eye  disease  has 
not  yet  been  definitely  established. 


INDEX 


Abducens  nerve,  2,  6 

paralysis  of,  60 
Abrasion  of  the  cornea,  140 
Abscess  of  the  lacrymal  gland,  88 

of  the  lacrymal  sac,  90 

of  the  orbit,  loi 
Absolute  glaucoma,  i  78 
Accommodation,  46 

in  glaucoma,  176 

in  hyperopia,  53 
Acetate    of   lead    in    follicular   conjunc- 
tivitis, 122 
Acid  burns,  1 2  7 
Acoin,  219 
Actual  cautery,  224 
Acute  trachoma,  i  20 
Advancement  of  an  ocular  muscle,   65 , 

69,  71 
Albargin,  224 
Albinism,  72,  165 
Albuminuric  retinitis,  197 
Alcoholic  amblyopia,  205 
Alternating  strabismus,  67 
Alum,  22s 
Alypin,  219 
Amaurosis,  210 

partialis  fugax,  212 
Amblyopia,  210 

central,  204 

congenital,  210 

from  alcohol,  205 

from  carbon  bisulfid,  206 

from  quinin,  206 

from  tobacco,  205 

hysterical,  21 1 

simulated,  2 1 1 

with  strabismus.  68 
Ametropia,  52 
Ammoniated  mercury,  226 
Anemia  of  the  retina,  191 
Anesin,  219 


Anesthesia  by  cocain,  2 1 8 

by  holocain,  219 

general,  218 

local,  218 

of  the  cornea,  140,  148,  178 
Anel's  syringe,  94 
Aneurism  in  the  orbit,  104 
Angioma,  129 

Angle  of  the  anterior  chamber,  20 
Anisometropia,  58 
Ankyloblepharon,  80 
Anomalies  of  the  puncta  and  canaliculi , 

89 
Anterior  capsule  of  the  lens,  29 

chamber,  13,  20 

ciliary  arteries,  18,  22,  27 

polar  cataract,  185 

pole  of  the  eyeball,  1 5 

synechia,  137,  145 
Antimetropia,  58 
Antiseptics,  222 
Antitoxin,  1 1 4 
Aphakia,  190 
Apoplexy,  pupil  in,  152 
Aqueous  chamber,  13,  22 

humor  secreted  and  excreted,  i  74 
Arachnoid  sheath  of  the  optic  nerve,  32 
Arcus  senilis,  146 
Argentamin,  224 
Argyll- Robertson  pupil,  152,  208 
Argyria,  108 
Argyrol,  224 

Arteria  centralis  retinae,  30 
Arterial  pulsation  in  glaucoma,  177 
Associated  movements  of  ocular  mus- 
cles, S9 
Asthenopia,  70 
Astigmia,  56 
Astringents,  224 
Atrophy  of  the  ball,  172,  179 

of  the  optic  nerve,  208 


231 


232 


Atropin  sulfate,  220 

in  iritis,  156 

in  corneal  ulceration,  141 
Axis  of  the  eyeball,  14 

Bacillus  of  diphtheria,  113 
Balance  of  the  eye  muscles,  S9 
Bichlorid  of  mercury,  222 
Biconcave  lenses,  42 
Biconvex  lenses,  42 
Binasal  hemianopsia,  213 
Biniodide  of  mercury,  223 
Binocular  field  of  vision,  49 
Bitemporal  hemianopsia,  213 
Black  eye,  85 

Blennorrhea,  chronic  conjunctival. 
Blepharitis,  73 
Blepharospasm,  81 
Blindness,  simulated,  211 
Blood  vessels  of  the  choroid,  26 

of  the  eye,  3 

of  the  iris,  22 

of  the  retina,  30 
Borax,  223 
Boric  acid,  223,  226 
Boroglycerid,  225 
Bowman's  membrane,  1  s 

probes,  92 
Brain,  tumor  of,  204 
Bright's  disease,  197 
BuUer's  shield,  1 1 1 
Burns  by  acids,  127 

by  lime,  127 

by  powder,  126 

Calomel,  226 

in  interstitial  keratitis,  13s 

in  phlyctenular  keratitis,  132 
Camphor,  225 
Canal  of  Cloquet,  29 

of  Schlemm,  19,  151 

the  hyaloid,  29 
Canaliculus,  anatomy  of,  10 

obstruction  of,  90 
Canthotomy,  1 1 1 
Canthus,  external  and  internal,  8 
Capsule  of  the  lens,  28 

of  Tenon,  3 

inflammation  of,  103 
CarboHc  acid,  223 
Carcinoma,  86,  173 
Caries  of  the  orbit,  99 


Carotid  ligation  and  compression  of,  104 
Caruncle,  n 
Cataract,  185 

anterior  polar,  185 

cortical,  187 

lamellar,  186 

nuclear,  187 

posterior  polar,  186 
Catarrhal  conjunctivitis,  105 

chronic,  107 
Cautery,  140,  194 
Cellulitis,  orbital,  loi 
Centrad  of  Dennett,  38 
Chalazion,  75 
Chemosis,  109 
Chiasm,  33 
Chloretone,  219 
Choked  disc,  203 
Chorio-capillaris,  27 
Choroid,  anatomy  of,  25 

diseases  of,  165 
Choroiditis,  165 

central,  168 

disseminate,  167 

exudative,  165 

myopic,  169 

plastic,  1 6s 

purulent,  171 

syphilitic,  168 
Cilia,  8 
Ciliary  arteries,  22,  26,  27 

body,  anatomy  of,  22 
diseases  of,  158 

ganglion,  24 

muscles,  22 

nerves,  22 

processes,  22 
Circulus  arteriosus  iridis  major,  22 
minor,  22 
Circumcomeal  injection,  iS4 
Cocain  hydrochlorate,  218,  219 
Cold  applications,  106,  no,  217 
Color  blindness,  central,  204 

congenital,  50 

perception,  49 
Color  of  the  iris,  1 9 
Commissure,  optic,  33 
Concave  lens,  41 
Concavoconvex  lens,  42 
Comitant  strabismus,  66 
Congenital  amblyopia,  210 

cataract,  185 


233 


Congenital  color  blindness,  so 
Conical  cornea,  147 
Conjugate  foci,  40 
Conjunctiva,  anatomy  of,  10 

diseases  of,  105 
Contraction  of  the  pupil,  152 
Convergence,  47 
Convergent  strabismus,  67,  70 
Convex  lens,  39 
Convexoconcave  lens,  42 
Copper  sulphate,  224 
Cornea,  anatomy  of,  i  s 

diseases  of,  130 
Cortex  of  the  lens,  29 
Cortical  cataract,  187 
Cover  test,  70 
Crab  lice,  85 
Crede's  method.  1 1  2 
Crossed  diplopia,  63 
Croupous  conjunctivitis,  1 1  2 
Crystalline  lens,  anatomy  of,  28 

diseases  of,  1 84 
Cuneus,  34 
Cuprol,  22s 

Curvature  of  the  cornea,  56 
Cyclitis,  158 
Cyclodiallsis,  181 
Cycloplegics,  220 
Cylindric  lens,  42 
Cysts  of  the  conjunctiva,  129 

Dacryocystitis,  acute,  94 

chronic,  90 
Dacryops,  89 
Daturin  sulfate,  221 
Day  blindness,  215 
Decussation  of  the  optic  nerves,  33 
Degenerative  changes  in  glaucoma,  1 79 
Deposits  on  the  cornea,  157 
Dermoid  tumors,  129 
Descemitis,  156 
Descemet's  membrane,  1 7 
Desmarre's  elevators,  no 
Detachment  of  the  retina,  200 
Deviating  eye,  60 
Diagnostic  table,  182,  183 
Dilatation  of  the  pupil,  152 
Dionin,  227 
Diopter,  44 

Diphtheritic  conjunctivitis,  1 1 2 
Diplo-bacillus  of  Morax  and   Axenfeld, 
106,  141 


Diplopia,  61,  67 

Disinfectants,  222 

Dislocation  of  the  lacrymal  gland,  89 

of  the  lens,  184 
Divergent  strabismus,  67 
Double  vision,  61 
Duboisin  sulfate,  221 
Dural  sheath  of  the  optic  nerve,  32 

EccHYMOsis  of  the  lids,  8s 

sub-conjunctival,  128 
Ectropion,  78 
Eczema  of  the  lids,  84 
Eldridge-Green  theory,  s  i 
Electric  ophthalmia,   191 
Electrolysis  in  trichiasis,  77 
Elevators,  Desmarre's,  iio 
Embolism  of  the  retinal  artery,  192 
Emmetropia,  45 
Emphysema  of  the  lid,  too 
Encephalocele,  97 
Endothelium  of  the  cornea,  i  7 
Entropion,  78 

Ephedrin  hydrochlorate,  220 
Epilation,  77 
Epiphora,  73,  87 
Episclera,  the     18 
Episcleritis,  149 
Epithelioma,  86,  129 
Epithelium  of  the  cornea,  15 
Equator  of  the  ball,  1 5 

of  the  lens,  29 
Equilibrium    of    the     ocular     muscles, 

S9 
Erysipelas  of  the  lids,  86,  102 
Eserin,  221 

in  glaucoma,   181 
Esophoria,  70 
Esotropia,  67 
Eucain,  219 

Euphthalmin  hydrochlorate,  220 
Eversion  of  the  punctum,  89 
Excavation  of  the  disc,  177 
Exciting  eye,  iS9 
Exclusion  of  the  pupil,   IS3 
Exophoria,  70 
Exophthalmos,  98 
Exostosis,  100 
Exotropia,  67 
External  canthus,  8 

ophthalmoplegia,  60 

palpebral  ligament,  6 


234 


INDEX. 


External  rectus  muscle,  3 
Eyeball,  anatomy  of,  1 2 

Facial  nerve,  6 

paralysis  of,  82 
False  image,  62 
Far  sight,  52 

Field  of  vision,  48,  176,  199 
Fifth  nerve,  2,  12.  15 
Fistula  of  lacrymal  sac,  95 
Fixing  eye,  60 
Fluorescin,  228 
Focal  distance  of  a  lens,  40 
Follicular  conjunctivitis,  121 
Fontana,  spaces  of,  21,  174 
Foreign  body  in  the  cornea,  147 

in  the  eyeball,  161 

in  the  vitreous,  164 
Formalin,  222 
Fornix,  conjunctival,  1 2 
Fourth  nerve,  2,  6 
Fovea  centralis,  30 
Fulminating  glaucoma,  1 78 
Fusion  faculty,  69 

Galvano  cautery,  140,  224 
Ganglion,  the  ciliary,  24 
Glands  of  Moll,  8 
Glaucoma,  174 
Glioma  of  the  retina,  201 
Gonococcus  of  Neisser,  109 
Gonorrheal  conjunctivitis,  108 
Granular  conjunctivitis,  115 
Gumma  of  the  iris,  154 

Halos  around  lights,  176 

Head,  position  of  in  strabismus,  64 

Headache,  64,  70 

Hemeralopia,  215 

Hemianopsia,  213 

Hemorrhage,  intra-ocular,  163,  173,  180, 

198 
Herpes  zoster  ophthalmicus,  84 
Heteronymous  diplopia,  63 
Heterophoria,  69,  70 
Holocain  hydrochlorate,  219 
Homatropin,  220 
Homonymous  diplopia,  63 

hemianopsia,  213 
Hordeolum    74 
Horner's  muscle,  2,  6 
Hot  applications,  217 


Hutchinson's  teeth,  134 
Hyaloid  artery,  29 

canal,  29 

fossa,  28-29 

membrane,  29 
Hyoscyamin  hydrobromate,  221 
Hyperemia  of  the  conjunctiva,  105 

of  the  retina,  191 
Hyperopia,  52,  67 
Hyperostosis,  100 
Hyperphoria,  70 
Hypertropia,  67 
Hypopyon,  138 
Hysterical  amblyopia,  211 

blepharospasm,  81 

Iced  compresses,  106,  no 
Ichthalbin,  228 
Ichthyol,  228 
Illumination,  oblique,  148 
Image,  real  and  false,  62 
Inferior  rectus  muscle,  3 

oblique  muscle,  4 
Infiltration  of  the  cornea,  130,  133,  137 
Infra-orbital  foramen,  2 

groove,  2 
Injection,  ciliary,  154 

conjunctival,  105 
Injuries  of  the  orbit,  100 
Insertion  of  the  recti  muscles,  4 
Insufficiency  of  ocular  muscles,  69 
Internal  canthus,  8 

ophthalmoplegia,  60 

palpebral  ligament,  6 

rectus  muscle,  3 
Interstitial  keratitis,  132 
Intra-ocular  tension,  174 

muscular  injections,  229 
Iodoform,  226 
Iridectomy,  144,  180 
Iris,  anatomy  of,  19 

diseases  of,  152 
Iritis,  plastic,  153 

serous,  136 

suppurative,  156 
Isometropia,  58 

Jequirity,  227 

use  of,  in  pannus,  119,  144 
Jequiritol,  227 

Jews,  predisposition  to  trachoma,  ii8 
Jonnesco's  operation,  180 


235 


Keratitis,  interstitial,  132 

phlyctenular,  130 

punctate,  156 

vascular,  143 
Keratoconus,  147 
Klebs-Loffler  bacillus,  113 
Knapp's  trachoma  forceps,  i  20 

Lacrymal  apparatus,  anatomy  of,  9 

diseases  of,  87 

gland,  9 

dislocation  of,  89 
fistula  of,  89 

sac,  I,  10 

fistula  of,  95 
Lagophthalmia,  82 
Lagrange's  operation,  180 
Lamellar  cataract,  1 86 
Lamina  cribrosa,  18 

basilis,  27 

fusca,   19.  2S 

vasculosa,  26 
Latent  squint,  69 
Lens,  crystalline,  anatomy  of,  28 

diseases  of,  184 
Lenses,  concave,  41 

convex,  39 

cylindrical,  42 
Lenticular  astigmia,  5  7 

ganglion,  24 
Leucoma,  144 

Levator  palpebne  supcrioris,  s 
Lice,  crab,  85 
Lid  clamp,  76,  85 

speculum,  190 
Lids,  anatomy  of,  6 

diseases  of,  73 
Ligamentum  pectinatum,  20 
Ligation  of  the  common  carotid,  104 
Light.  35 

rays.  35 
Light,  perception  in  cataract,  189 
Lime  bums,  127 
Lipoma,  129 
Locomotor  ataxia,  152 
Long  ciliary  arteries,  22,  27 

nerves,  24 
Lupus  of  the  lids,  86 
Lymph  spaces  of  the  cornea,  1 7 

Macula  lutea,  30 

of  the  cornea,  144 


Malingering,  21 1 
Massage  of  the  cornea,  13s 
Megalopsia,  166,  195 
Meibomian  glands,  8 
Membrane  of  Bowman,  15 

of  Descemet,  i  7 
Membranous  conjunctivitis,  112 
Meningocele,  97 
Meridians  of  the  eyeball,  15 
Metamorphopsia,  166,  195 
Micropsia,  166,  195 
Milium,  86 

Miner's  nystagmus.  72 
Mixed  trachoma,  116 
Moll's  glands,  8 
MoUuscum  contagiosum,  86 
Monolateral  strabismus,  67 
Morbid  growths  in  conjunctiva,  128 
MuUer's  muscle,  55 
Musc;e  volitantes,  i6i 
Muscles,  ocular,  3 
Muscular  equilibrium,  S9 
Mydriasis,  152 
Mydriatics,  152,  219,  220 
Myopia,  S4,  68 
Myopic  crescent,  t  70 
Myosis,  152 
Myotics,  152,  221 

Nargol,  224 

Nausea  in  paralytic  strabismus,  64 

Nasal  duct,  10 

stricture  of,  91 
Nebula  of  the  cornea,  144 
Necrosis  of  the  orbit,  99 
Negative  focus,  41 
Nerve,  optic,  31,  203 
Nerves  of  ocular  muscles,  6 
Neuro-paralytic  keratitis,  139 
Neuro-retinitis,  194.  204 
Nevus,  86,  129 
Nictitation,  81 
Night  blindness,  199,  214 
Nosophen,  226 
Nuclear  cataract,  187 
Nucleus  of  the  lens,  29 
Nyctalopia,  214 
Nystagmus,  71 

OBLiyuE  illumination,  148 
muscles,  4 
position  of  head  in  squint,  64 


236 


Obliteration  of  the  puncti,'  90 

of  lacrymal  sac,  96 
Occlusion  of  the  pupil,  153 
Ocular  muscles,  3 
Oculomotor  nerve,  6 
Opacity  of  the  comer,  144 

of  the  vitreous,  162 
Ophthalmia  neonatorum,  108 
Ophthalmic  artery,  3 

vein,  2 
Ophthalmoplegia,  external,  60 

internal,  60 

total,  60 
Optic  commissure,  33 
Optic  disc,  30,  31 

foramen,  2 

nerve,  2,  31,  203,  208 

tracts,  33 
Optics,  35 
Ora  serrata,  30 
Orbicularis  muscle,  i ,  6 
Orbits,  anatomy  of,  i 

diseases  of,  97 
Orbital  cellulitis,   loi 
Orthophoria,  70 
Outer  canthus,  8 

Palpebral  fissure,  8 
Pannus  117,  143 
Panophthalmitis,  139,   171 
Papilke  of  conjunctiva,  1 1 
Papillary  trachoma,  115 
Papillitis,  203 
Papilloma,  129 
Parallel  rays,  45 
Paralysis  of  ocular  muscles,  60 
Paralytic  ectropion,  78 

strabismus,  60 
Parenchymatous  keratitis,  132 
Paresis  of  ocular  muscles,  60 
Pectinate  ligament,  20 
Perception  of  colors,  49 
Perforation  of  the  cornea,  137 
Perichoroidal  space,  19 
Pericorneal  injection,  154 
Periostitis,  97 
Periostosis,  100 
Permanganate  of  potash,  223 
Peroxide  of  hydrogen,  222 
Phlyctenular  conjunctivitis,  130 

keratitis,  130 
Phthiriasis,  85 


Phthisis  bulbi,  172,  179 

Physiology  of  the  eye,  45 

Pial  sheath  of  the  optic  nerve,  32 

Pilocarpin  hydrochlorate,  221 

Pinguecula,  125 

Planoconcave  lenses,  42 

convex  lenses,  42 
Plica  semilunaris,  11 
Position  of  eye  in  the  orbit,  1 2 
Posterior  chamber,  13,  21 

ciliary  arteries,  1 8 
nerves,  18 

polar  cataract,  186 

pole  of  eyeball,  15 

staphyloma,  170 

synechia,  134,  153 
Powder  burns,  126 
Presbyopia,  47 
Primary  colors,  50 

deviation  of  squinting  eye,  61 
Principal  axis  of  a  lens,  40 

focus  of  a  lens,  40 
Principal  meridians  of  cornea,  57 
Prism  diopter  of  Dennett,  38 
Prisms,  38 

Probes  for  nasal  duct,  92 
Proliferative  uveitis,  160 
Proptosis,  98 

Projection  of  retinal  images,  62 
Protargol,  224 
Pseudo-glioma,  171,  202 
Pterygium,  124 
Ptosis,  82 

Pulsating  exophthalmos,  104 
Puncta  lachrymalia,  10 
Pupil,  19,  152 
Pupillary  adhesions,  153 
Purulent  conjunctivitis,  108 
Pus  in  the  anterior  chamber,  138,  154 
Pyoktanin,  223 

Qumm  amblyopia,  206 

Radium,  228 

Rays  of  light,  35 

Real  image,  62 

Recti  muscles,  3 

Refracting  media  of  the  eye,  45 

Refraction,  35-45 

Retina,  anatomy  of,  30 

diseases  of,  191 
Retinitis,  194 


INDEX. 


237 


Retinitis,  albuminuric    197 

diabetic,  197 

hemorrhagic,  198 

pigmentosa,  199 

serous,  194 

syphilitic,  198 
Retro-bulbar  neuritis,  203,  204 
Roentgen  ray,  228 
Rupture  of  the  choroid,  173 

Sarcoma,  86,  129,  173 
Schlemm's  canal,  19,  174 
Sclera,  anatomy  of,  18 

diseases  of,  149 
Scleritis,  150 
Sclerotomy,  180 
Scopolamin  hydrobromate,  221 
Scotoma,  165,  176,  204,  212 
Scrofulous  conjunctivitis,  131 
Second  sight,  188 
Secondary  deviation  in  squint,  61 
Semilunar  fold,  1 1 
Septum  orbitale,  8 
Serous  iritis,  156 

cyclitis,  158 
Serum  therapy,  229 
Short  ciliary  arteries,  26 

nerves,  24 
Short  sightedness,  S4 
Silver  nitrate,  223 
Simple  colors,  50 
Simulation  of  blindness,  211 
Sixth  nerve,  2,  6 
SHtting  of  canaliculus,  92 
Snow  blindness,  191 
Spaces  of  Fontana,  21,  174 
Spasm  of  the  orbicularis,  81 
Sphenoidal  fissure,  2 
Spheno-maxillary  fissure,  2 
Spheric  lenses,  39 
Spring  catarrh,  123 
Squint,  60 

Staphyloma,  139,  i45.  iSi.  '70 
Stovaine,  219 
Strabismus,  paralytic,  60 

comitant,  66 
Stricture  of  the  nasal  duct,  91 
Stye,  74 

Subarachnoid  space,  33 
Subconjunctival  ecchymosis,  i  28 

injections,  228 
Subdural  space,  32 


Substantia  propria  of  cornea .  1 5 
Superior  oblique  muscle,  4 

rectus  muscle,  3 
Suprachoroidea,  25 
Supra-orbital  foramen,  2 

-renal  extract,  227 
Symblepharon,  126 
Sympathetic  nerve,  20 

ophthalmia,  158 
Sympathizing  eye,  159 
Synchisis  of  vitreous,  162 
Synechia,  137,  138.  i4S.  i53 
Syphilitic  retinitis,  198 

ulcer  of  conjunctiva,  i  28 

ulcer  of  lids,  86 

Tannik,  22s 

Tarsorrhaphy,  82 

Tarsus,  anatomy  of,  6 

Tears,  secretion  of,  87 

Tenon's  capsule,  3 

Tenotomy,  65,  69,  71 

Tension,  intra-ocular,  174 

Tensor  tarsi,  2,  6 

Tests  for  malingerers,  211 

Third  nerve,  2,  6,  19 

Thrombosis  of  retinal  vein    102 

of  sinuses,  86 
Tincture  of  iodin,  223 
Tobacco  amblyopia,  205 
Tonic  spasm  of  orbicularis,  ."^i 
Total  ophthalmoplegia,  6c 
Trachoma,  1 1  5 

acute,  I  20 
Trichiasis,  77 
Trikresol,  222 
True  image,  62 
Tuberculosis  of  the  conjunctiva    i  79 

of  the  choroid,  173 
Tumors  of  the  orbit,  103 
Turbidity  of  the  aqueous  humor    154 

Ulceration  of  the  cornea,  136 
Uveal  tract,  13 

Vaccine  therapy,  229 
Vascular  keratitis,  143 
Vena;  vorticosi",  18,  27 
Vernal  conjunctivitis,  123 
Vertigo  in  paralytic  squint,  64 
Virtual  focus,  41 


=38 


Vitreous  humor,  anatomy  of,  29 
diseases  of,  161 
hemorrhage,  163 

Week's  bacillus,  106 
Whooping  cough,  128 
Winking,  habit  of,  8i 

Xanthelasma,  86 
Xeroform,  226 
Xerosis  bacillus,  75  • 


X-ray,  86,  10 1,  164,  228 

Yellow  spot  or  macula  lutea,  30 

oxid  of  mercury,  226 
Young-Helmholtz  theory  of  color  per- 
ception, so 

Zinc  chlorid,  225 

sulfate,  225 
Zonula  of  Zinn,  29 
Zonular  cataract,  162 


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